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  • 2021-10-30为什么冥王星不是行星?伙计们,它完了,没救了。我知道,我知道,当我第一次听到新闻时Guys, it’s done. It’s over. I know, I know, I was as upset as you were when I first 我和你们一样沮丧。我们都学过这样的歌谣来帮助记忆行星,heard the news. We were taught these songs and sayings to help us remember the planets, 现在它们被毁了。但是冥王星从2006年就已经不是颗行星了,所以,and now they’re all ruined. But Pluto hasn’t been a planet since, like, 2006, so it’s 该向前看了。但如果你从已被摧毁的音乐和Meg Ryan的电影中看看的话time to move on. But if you’ve gone through all your breakup music and Meg Ryan movies 你还是不能避开冥王星,所以我们今天在 SciShow Space这里会and you still can’t get over Pluto, then we here at SciShow Space will get out the 拿出冰淇淋,和你一起蜷缩在长椅上,聊聊这事是怎么发生的。ice-cream, cuddle up with you on the couch, and talk about how this could’ve happened. 在2006年布拉格的第26次国际天文学联合大会上,冥王星被降级Pluto was demoted at the 26th general assembly of the International Astronomical Union in 这是个有争议的决定。有天文学家希望保留它Prague in 2006, and it was a controversial decision. There were astronomers who wanted 但他们唯一能争论的是传统。曾经没有,现在也没有to keep it, but the only argument they could make was tradition. There was, and is, no 科学依据称呼冥王星为行星。scientific justification for calling Pluto a planet. It’s a thing out there in the 它是颗在小行星带柯伊伯带内的星星,只有它比海王星远并且它更大些Kuiper belt which is like the asteroid belt, only it’s out past Neptune and it’s a 柯伊伯带大约有上万亿天体。一百万个百万天体!lot bigger. There are about a trillion things in the Kuiper belt. A million million things! 并且几乎所有这些天体都是冰块和石块,就像冥王星。And nearly all of those things are chunks of ice and rock, like Pluto. Pluto is just 冥王星只是我们发现的第一个。the first one that we saw. 冥王星的确比其中的一些天体大,但不是柯伊伯带中最大的天体And Pluto is pretty big for one of those things, but it’s not the biggest thing in the Kuiper 那是厄里斯的头衔,其质量大了25%,是冥王星距太阳距离的两倍belt. That title goes to Eris which is about 25% bigger by mass and twice as far from the 也有其他的大天体,例如妊神星和鸟神星和谷神星sun as Pluto. There are other big things too, like Haumea and Makemake and Ceres, which 位于火星和木星中间的小行星带中,让其实际上成了一个小个子。科学家is in the asteroid belt between Mars and Jupiter, making it practically a local. Scientists 预言柯伊伯带将有上百个其他大天体predict that there may be up to a hundred other big things out there in the Kuiper belt 等待被发现。但是了解了上百颗行星just waiting to be discovered. But having over a hundred planets would have made those 会让那些歌谣和我们在小学学到的说法变得真的真的很长。songs and sayings we learned in elementary school really, really long. And that’s really 这才是我们将冥王星降级的关键所在,因为如果我们管冥王星叫行星的话,the crux of why we had to downgrade Pluto because if we call Pluto a planet we’d have 我们也得同样称呼如此多的其他天体,“行星”这个词就没有用了to call so many other things planets too that the word ‘planet’ would stop being useful. 所以在2006年,天文学家决定要成为一颗行星,天体必须:环绕太阳飞行,So in 2006, astronomers decided that to be a planet an object had to: orbit the sun, 有足够的引力使其或多或少地成为球形,have enough gravity to pull itself into a more or less spherical shape, and have cleared 已经清除自己轨道上的所有东西。最后一条是冥王星不符合的地方pretty much everything else out of its orbital path. The last one is where Pluto falls short. 冥王星仅比它轨道上的其他物体重0.07倍。地球,Pluto is only 0.07 times the mass of everything else in its orbit. Earth, just to give you 只是给你一个感受的角度,比轨道上其他物体重1.7百万倍some sense of perspective, is 1.7 million times the mass of everything else in its orbit. 但是国际天文联合会并非完全无情。But the International Astronomical Union wasn’t completely heartless. It came up with a new 其创立了天体的一个新分类,只包括前两个标准。category of celestial objects that satisfies only the first two criteria. We call them 我们叫它矮行星。并且为了让这个特殊的冥王星常驻心中,他们决定dwarf planets. And in honor of this special place Pluto holds in our hearts, they decided 管所有海王星外的行星叫Plutoids,这……真是太好了。to call all dwarf planets past Neptune plutoids which is… It’s pretty sweet. And the same 同年,天文学家决定不能再认为冥王星是行星,year astronomers decided Pluto could no longer be considered a planet, NASA launched the NASA发布了新视野号以拜访冥王星。新视野号会New Horizons spacecraft with a mission of visiting Pluto. New Horizons will do a dramatic 在2015年7月激动人心地飞掠冥王星和它的月亮们,并传回许多照片和信息flyby of Pluto and its moons in July of 2015 and send back lots of photos and information ,其将会史无前例地告诉我们关于我们喜爱的小矮行星。并且它也会that will tell us more than ever about our favorite little dwarf planet. And it will 捎去我个人最深的祝福also carry my personal and deepest good wishes. 感谢观看这期SciShow Space,谢谢所有的Subbable订阅者Thanks for watching this episode of SciShow Space, and thanks to all of our Subbable subscribers 让这个频道成为可能。如果你想要支持我们并且获得一些很赞的装备who make this channel possible. If you’d like to support us and score some cool gear, 去subbable.com了解更多。如果你对想看的一集节目有问题或想法go to subbable.com to learn more. And if you have questions or ideas for an episode you’d 你可以在脸书和推特找到我们并在下面评论like to see, you can find us on Facebook and Twitter and in the comments below, and if 而如果你想和我们一起变得更聪明,只需去youtube.com/scishowspace并订阅you want to keep getting smarter with us, just go to youtube.com/scishowspace and subscribe.
  • 2021-10-30怎样能睡着?美国有六千万人深受失眠困扰 因此以下现象就不足为奇了As many as 60 million Americans suffer from insomnia, so it’s not much of a surprise 谷歌发了份关于全球英语口语者的热搜问题列表that, when Google sent us their list of the most asked questions in the English-speaking 而 我怎样才能睡着 这个问题接近榜首world, “How Can I Fall Asleep” was pretty close to the top. 六千万人!Sixty million people! 这太不可思议了 你知道 不可能有人不需要睡眠That’s weird since, y’know, it’s literally impossible NOT to sleep. 如果你就是半夜睡不着而谷歌“有助于睡眠的方法”的人之一And if you’re one of those people who’s up in the middle of the night Googling sleep solutions 那么了解一些睡眠科学可能会对你有所帮助it might help you to learn a little about the science of sleep. 这是世界上困扰最多人的问题This is The World’s Most Asked Questions. [Intro] 你首先需要了解 你无法进入睡眠The first thing you should know if you’re having a hard time getting some shuteye 是因为你过于亢奋而无法在正常时间内睡着 无法每晚准时上床is that you are wired to sleep regular hours going to bed the same time each night 以及每早准时起床and waking up at the same time each morning. 拥有规律的起床时间好像与你入睡的能力有极高的关联Having a regular wake-up time seems to correlate pretty highly with the ability to fall asleep 一贯如此consistently. 因为它使你与你的生理状态(也被称为生理节律)保持均衡This is because it keeps you aligned with what’s known as your circadian rhythm, your 即你的身体与日夜周期规律保持同步的自然倾向body’s natural tendency to stay in sync with the cycles of day and night. 你知道什么是控制你生理节律的最大因素吗And you know what controls your body’s circadian rhythm more than anything else? 是光Light. 让你入睡的最大助力来自于身体激素 它们降低你的心率A lot of the help you get falling asleep comes from hormones — they lower your heart rate 降低你的血压 让你基本上放松下来and reduce your blood pressure and basically let you relax. 这关键激素就是荷尔蒙褪黑色素 它受你是否暴露在光下控制The key player here is the hormone melatonin, and it’s regulated by your exposure to light. 在黑暗中 它大量产生In darkness, it flows freely. 但是当你暴露在光线中 无论是自然的还是人造的 这种褪黑色素的释放But when you’re exposed to light — whether natural or artificial — the release of melatonin 就会停止stops. 你知道这代表什么吗So you know what that means? 床上不能有手机和笔记本电脑!No phones or laptops in bed! 电子产品发射出的光困扰着你的身体 使其无法知道什么时间该入睡The light emitted by electronics confuses your body into not knowing that it’s time to sleep. 因此科学家表示你在至少入睡一个小时前就应该远离电子屏幕So scientists suggest at least an hour of screen-free time before bed…though I am 虽然我个人完全无法做到completely incapable of that myself. 而另一个明显的睡眠敌人就是咖啡因Another obvious enemy of sleep: caffeine. 即使你认为在晚饭后的一杯咖啡可能只会影响你大约一个小时Even though you might think that cup of coffee after dinner might only affect you for an hour or so 但研究表明咖啡因消耗需要持续将近十二个小时studies have shown that caffeine consumption as much as TWELVE HOURS before 在你认为自己失眠之前bedtime is linked with insomnia. 甚至你看待睡眠的方式能够影响你的睡眠模式And even the way you think about sleep can affect your sleep patterns. 对于自己不能够得到充足睡眠感到焦虑是一种导致失眠的常见因素Worrying about not getting enough sleep is a common enough cause of insomnia that it 它有自己的名字 入睡性失眠has its own name, Sleep Onset Insomnia. 但你知道真正不可思议的是什么吗But you know what’s really weird? 在我们认为自己没有入睡的很大一部分时间里 实际上是处于睡眠中的A lot of the time, when we feel like we can’t sleep — we actually ARE sleeping. 当科学家们将处于第一二睡眠阶段的病人叫醒时 超过百分之六十的人When scientists rouse patients in the first or second stages of sleep, more than 60% of 说他们没有睡着 即使他们睡着了them say that they weren’t sleeping, even though they were. 当然 现在有药物能够帮助你入睡Now, of course, there’s a whole class of medications that will help you sleep, from 从抗阻安到以安眠药为代表的药物 包括安比恩和舒乐安定antihistamines to the pharmaceuticals known as hypnotics, which include Ambien and Lunesta. 但研究显示当病人在服用药物后更快入睡But research has shown that while patients can fall asleep faster on hypnotics, the effect 药物所起到的作用是很小的 只增加了十五分钟的睡眠时间is small, adding only about 15 minutes to their sleep times. 也有研究显示我们的意志力比药物具有更为显著的效果Other studies indicate that our minds are significantly more powerful than any medications. 在双盲实验中 被告知服用了安眠药的病人In double-blind studies, patients who were simply told that they were taking a sleep 比被告知未服用的病人要更快入睡drug ended up sleeping far better than patients who were told they weren’t. 因此 如果你想知道该如何入睡 答案已经很明显了So, if you want to know how to sleep, the answer is right there in your head. 作为我们回答热门问题工作的一部分 我们向观众提问了Now as part of our work answering the world’s most asked questions, we asked you, our SciShow 一些问题 其中有你每晚睡几个小时viewers, a few questions…and one was how many hours per night you sleep. 但情况并不乐观 仅仅百分之十的受访者睡眠时间超过八个小时And it’s bad news: Only 10% of you are sleeping more than eight hours per night, and eight 仅八又二分之一满足了医生推荐的睡眠量and a half is the doctor-recommended amount. 超过一半的人表示自己一周内至少会有一次难以入眠And OVER HALF of you report having trouble getting to sleep at least once per week. 接下来是无意义统计时间And now it’s time for MEANINGLESS CORRELATIONS!!! 我们通过足够的数据得出结论 睡眠质量最好的国家The best sleepers for countries where we had enough data to make any sort of judgement 是沙特阿拉伯 百分之七十六的研究表明他们鲜少经历失眠were Saudi Arabians, with 76 percent reporting that they experience insomnia infrequently 或者说从不失眠or never. 大部分欧洲国家比一般国家在睡眠上得分更高 其中荷兰人 俄罗斯人以及西班牙人的Most of Europe scored better than average, with The Netherlands, Russia, and Spain all 睡眠质量都相对较高sleeping relatively soundly. 而说英语的国家 比如美国 英国和澳大利亚得分最低The English speakers in the US, UK, and Australia all had some of the worst scores. 最后 毫不意外 我们的调查发现And, finally, unsurprisingly, our staggeringly unscientific survey reports that people who 经常饮用咖啡 苏打水 能量饮料和茶的人往往更容易commonly drink coffee, soda, energy drinks or tea are all more likely to suffer from 经历失眠insomnia. 感谢大家的观看 特别感谢谷歌对我们关于热搜问题的分享Thanks for watching, and special thanks to Google for sharing their most asked questions with us. 在所有引人注目的问题里 你最想得知哪个答案Of all the fascinating questions in the world, which do you want answered most? 告诉我们 在脸书 推特或者下方的评论区 我们将会Let us know on Facebook or Twitter or in the comments down below and we will answer the 在每月末更新的视频中回答最棒的问题best questions in a new video at the end of the month. 别忘了带上标签#WMAQ 敬请期待本周更多视频Don’t forget to use the hashtag #WMAQ and stay tuned for more videos this week.
  • 2021-10-30行星位置变迁二十多年前 天文学家就在其他恒星系中观测到了行星It’s been more than twenty years since astronomers began detecting planets around other stars. 他们对此并不感到惊讶They weren’t surprised to find planets in other star systems. 有趣的是这些行星的排布方式使得天文学家们开始But they were surprised by how those planets were arranged, and they ended up having to 重新思考行星的形成问题rethink what they thought they knew about how planets form. 通常我们认为太阳系是一个标准的恒星系We used to think that our Solar System was pretty standard, as star systems go. 较小的四颗固态行星在内 其余四颗气态行星在外Our arrangement of four smaller inner rocky planets and four bigger outer gaseous ones 这样的分布是有物理学依据的:makes a lot of physical sense: 在温度极低的远日空间 大量分子聚集起来When you’re farther away from the Sun, space is colder, which allows more molecules to 便会形成体积庞大的行星condense and build up larger planets. 然而不久前 我们发现了首颗系外行星——第一颗发现于太阳系外的But then, we found our first exoplanet — the first planet we’d discovered outside of 行星our solar system. 它的存在证明了我们过去的理解是错误的And it revealed a situation we used to think was impossible. 这颗行星大小与土星相当The first exoplanet was a world the size of Saturn, orbiting more than seven times closer 轨道半径小于水星轨道的七分之一to its star than Mercury does to the Sun! 这颗行星距恒星太近 应该无法存在 因为较轻的气体There’s almost no way it could have formed so close to its star — all the light gases 还未来得及形成行星便已被蒸发would have boiled off before they could’ve formed a planet. 随着逐渐获取到的数据天文学家开始不断发现这种临近恒星的As astronomers collected more data, they started to find more and more of these big, gas planets, 大型气态行星 将它们命名为热木星which we now call Hot Jupiters, close to their stars. 他们意识到热木星是从某处迁移而来的They realized that Hot Jupiters migrated from somewhere else, and they started trying to 继而致力于弄清缘由figure out how. 自此以后 天文学家认识到在行星形成早期Since then, they’ve come to realize that planets can actually move around a lot in 其轨道是会产生较大变动的their early lives. 原行星盘是行星的形成区域Planets form in regions called protoplanetary disks, made up of the leftover gas and dust 主要由恒星生成之后残余的气体和灰烬构成after a star forms. 银河系中所有新生恒星的周围都有原行星盘We see these disks surrounding young stars all over our galaxy. 它们为固态物质的聚集创造了条件They provide a place for solid matter to clump together, and eventually, the largest clumps 最终 最大的物质团会重到足以吸引气体形成类似木星和土星一样的行星become massive enough to pull in gas, giving rise to worlds like Jupiter and Saturn. 一旦形成 这些新生行星仍暂时留在原行星盘中Once they form, these new planets are still embedded in the protoplanetary disk. 原行星盘是它们变轨的关键And that disk is the key to how they move around. 新生行星的引力将使周围的物质产生巨大波动A new planet’s gravity affects the nearby disk material, bunching it up into giant waves ——螺旋密度波called spiral density waves. 同样是这种波动使银河系形成悬臂 土星拥有了星环They’re the same kinds of structures that give galaxies their arms and Saturn’s rings 不仅如此there’re details. 行星轨道内部距恒星较近的区域有密度波 轨道外部There’s one density wave inside the planet’s orbit, closer to the star, and one outside 距恒星较远的区域也有密度波the planet’s orbit, on the side farther from the star. 距离恒星越近 引力便越强 行星运行速度便越快Now, the closer you are to a star, the harder its gravity pulls you and the faster you travel. 因此 随着时间推移 朝向恒星的密度波开始处于行星前方So, over time, the wave towards the star starts to creep ahead, while the one outside the 同时行星轨道外的密度波开始处于行星后方planet’s orbit starts to fall behind. 这些密度波是由物质构成的But these density waves are made up of actual, physical stuff and therefore exert gravity 因此也会影响自身的引力of their own. 因此前方的密度波会向前拖曳行星So that wave ahead of the planet is pulling it forward in its orbit, which gives the planet 给了它一些推动力 将其逐渐推离恒星a little boost in energy, sending it a bit farther from the star. 同时 处于行星后方的密度波正做着相反的事情Meanwhile, the wave behind the planet is doing the exact opposite. 它的引力将行星向后方拖曳 减少其动量Its gravity tugs the planet backwards, reducing its energy and forcing it to fall into a smaller 迫使行星降低轨道orbit. 如果这些外力正好平衡 行星轨道便不会再变化If these forces exactly balanced out, the planet wouldn’t move at all, but usually 但是通常情况下 原行星盘的密度分布是不均匀的the protoplanetary disk is less dense in some places than others. 这使得两密度波的拉力难以抵消That difference makes the pull of one wave more powerful than the other, so the planet 所以 行星轨道会产生变化moves. 在模拟环境下 这一推演过程切合行星的运动In simulations, this process is so effective at moving planets around that some scientists 一些科学家难以解释为何还会有如此多的行星幸存aren’t really sure why so many survive at all. 最终 他们有了这个解释热木星存在的理论So, finally an explanation for how those strange Hot Jupiters could exist where they do! 它们可能先在距恒星较远处形成They probably formed much farther away from their stars before migrating in to where they 然后才迁移到现在的轨道are now. 甚至我们太阳系的行星也是很久以前迁移过来的Even the planets in our own Solar System probably migrated long ago. 这个假说在法国提出后 被天文学家称为Nice模型Astronomers call this idea the Nice Model, after the city in France where it was developed. Nice模型认为 45亿年前 外部行星刚形成时The Nice Model says that when the outer planets were forming four and a half billion years 距离非常近ago, they were much more closely spaced than they are today. 随着时间推移盘内相互作用使它们运动到了现在的位置Over time, interactions with the disk drove them to where they are now, but they might 但迁移过程可能并不顺利have made some major detours along the way. 例如 木星可能在我们今天称为太阳系内部的区域Jupiter, for example, might have spent some time in what today we’d call the inner Solar 花费了一些时间System. 如果它运行到火星轨道附近此时两个行星都已形成If it wandered close to the orbit of Mars as both planets were forming, it could have 它可能戏剧性的变轻而成为红行星dramatically reduced the amount of material left to make the Red Planet. 这就解释了为什么在许多行星构造模型中This would help explain why many models of planet formation suggest that Mars should 火星本该和地球一样大 但实际却只有地球质量的十分之一be roughly Earth-sized, when really, it only has about a tenth of our mass! 海王星也许在初始时比天王星距太阳更近And Neptune may have started its life closer to the Sun than Uranus. 然后 在运动过程中 它们交换了位置Then, once they began to move, they would have swapped places. 这些行星位置不断变化It might have taken hundreds of millions of years for things to settle down to how we 至今可能已有上亿年see them today. 直到原行星盘中的气体和灰尘全部消散By that time, the disk of gas and dust would have blown away, leaving behind only the scattered, 只剩行星形成后留下的碎石rocky remains of planet formation. 当那些碎石遇到像木星样的行星时行星的引力会将它们推向太阳As those rocks encountered a world like Jupiter, the planet’s gravity could have flung them 同时 碎石也会推动木星一点点远离太阳towards the Sun — and in the process, propelled the gas giant just a little bit farther. 慢慢的 我们今天看到的太阳系便形成了——一次一块碎石Slowly, the Solar System we know today took shape — one rock at a time. 对太阳系外行星的研究使我们明白了And if our search for planets around other stars has taught us anything, it’s that 这是事物发展的唯一可能途径this is only one possible way things might have played out. 现在我们已经知道 行星形成后并不是原地不动的We now know that planets don’t just stay put after they’re formed — there are all 它们总是在变换轨道kinds of processes that can move them around. 感谢您观看这段SciShowThanks for watching this episode of SciShow Space, and thanks especially to our patrons 特别感谢Patreon 是他的帮助让节目持续到现在on Patreon who help make this show possible. 如果你想帮助我们继续制作这样的短片If you want to help us keep making episodes like this, just go to patreon.com/scishow 请去patreon.com/scishow了解更多to learn more. 别忘了去 youtube.com/scishowspace 订阅And don’t forget to go to youtube.com/scishowspace and subscribe!
  • 2021-10-30两年前我们对冥王星所知的最酷的事情当2006年新地平线号探测器出发前往冥王星时When New Horizons set off toward Pluto in 2006, 我们对我们将会在那里发现什么一无所知we had almost no idea what we would find there. 对于它的大小和组成我们有一点儿了解 但我们也就知道这么点We knew a little about its size and composition, but that was mostly it. 我们甚至都不知道它长什么样We didn’t even really know what it looked like. 2015年的7月14日 新地平线号抵达了冥王星 着实让我们开了眼Then, on July 14, 2015, New Horizons showed up at Pluto, and totally blew our minds. 我们发现冥王星系统是我们探索过的最酷的地方之一We found out the Pluto system is one of the coolest places we’ve ever explored. 所以为了庆祝探测飞行两周年纪念日So to celebrate the fly-by’s two-year anniversary, 这里有我们了解到的一些最令人兴奋的事情here are some of the most exciting things that we’ve learned. 第一个就是 上面有一个巨大的 超级可爱的心形First, there’s that giant, super cute heart, 科学家非正式地将它称为斯普特尼克平原which scientists informally called Sputnik Planum. 这个区域主要由缓慢流动的 冻结的氮气组成That area is made up mostly of slowly flowing, frozen nitrogen. 其中移动的冰块是太阳系最大的冰川之一The mass of moving ice is one of the largest glaciers in the solar system! 但最特别的是氮冰正在进行运流But what’s especially neat is that the nitrogen ice is undergoing convection, 作为材料的环流不断加热并冷却the circular current that forms as material heats up and cools down. 冥王星上十分寒冷 大概平均零下230摄氏度Pluto is pretty cold, at around -230 degrees Celsius on average. 但在冥王星核心处缓慢衰变的元素能创造出足够的热量But the elements slowly decaying in Pluto’s core create just enough heat 使得地下氮冰都变成软糊状to make underground nitrogen ice all soft and mushy. 然后 松软的冰上升到表面 冷却下来 接着再次沉入地下Then, that soft ice rises to the surface, cools down, and sinks underground again, 有点像一个巨大巧妙的熔岩灯kinda like a gigantic, groovy lava lamp. 许多科学家都没想到冥王星上会有如此活跃的地质运动A lot of scientists didn’t expect to see active geology on Pluto, 这也使得这次的发现令人惊叹不已which made this discovery an awesome surprise. 新地平线号还发现冥王星拥有大量的山脉New Horizons found that Pluto has plenty of mountains, too, 其中一些被甲烷冰所覆盖including some covered in methane ice. 还有一些山脉 比如一个叫做赖特山的And some of those mountains, like one called Wright Mons, 甚至可能是一座冰火山even look like they could be cryovolcanoes, or ice volcanoes. 当新地平线号飞掠的时候 我们没有看到任何活跃喷发的东西We didn’t see anything actively erupting when New Horizons flew by, 所以我们也不能确定 但是这些火山是有可能喷发出so we don’t know for sure, but these volcanoes might erupt 冰 氨 甲烷或氮冰的混合物的with a mixture of water ice, ammonia, methane, or frozen nitrogen. 对于一个如此遥远的小世界来说 这是相当奇妙的Which is pretty neat for a little world so far away. 有关冥王星的探索并没有局限于地面And the discoveries about Pluto weren’t limited to the ground, 或者它能喷发出什么东西or what could potentially erupt out of it. 新地平线号还发现了冥王星的天空是蓝色的New Horizons also found out that Pluto’s sky is blue. 就像我们的家园一样!It’s just like home! 除了低温 缺少阳光和有毒的空气以外That is, besides the freezing temperatures, lack of sunlight, and toxic air. 在地球上 天空之所以是蓝色的是因为大气中像氮气这样的分子会散射阳光Here on Earth, the sky is blue because molecules like nitrogen in the atmosphere scatter sunlight, 但在冥王星上是一种叫做索林的分子在进行散射but on Pluto, molecules called tholins do the scattering. 索林是一种复杂有机的分子 是由来自太阳的紫外线与冥王星大气中的Tholins are complex, organic molecules that form when UV light from the Sun reacts with 氮和甲烷发生反应而产生the nitrogen and methane in Pluto’s atmosphere. 索林本身是灰色或红色The tholins themselves are probably grey or red, 这会让冥王星表面蒙上一些它们的颜色and they help give Pluto’s surface some of its color. 但微小的体积让它们更容易散射蓝色光But their small size makes them perfect for scattering blue light. 噢 几十亿公里之外还有东西能让我们想到家乡 这真是太棒了Aww! There’s nothing like finding little reminders of home billions of kilometers away. 当飞掠冥王星的时候 新地平线号也对它的卫星进行了近距离的观测While it was flying past Pluto, New Horizons also got our closest look at Pluto’s moons: 卡戎 许德拉 尼克斯 斯蒂克斯以及克伯勒斯Charon, Hydra, Nix, Styx, and Kerberos. 在其中最大的卫星卡戎上有一些有趣的发现And the largest moon, Charon, had some fun surprises. 首先 它的北极呈现暗红色 新地平线号团队称它为“摩多”For one thing, its north pole, which the New Horizons team dubbed Mordor, is dark red, 冥王星可能和这种现象的形成有关and Pluto might have had something to do with that. 去年发表在《自然》杂志上的一篇文章上 科学家们提出In a paper published in the journal Nature last year, scientists suggested Charon’s 卡戎的北极呈现暗红色是冥王星的大气一直浸染所致pole is red because Pluto’s atmosphere is staining it. 冥王星大气中的甲烷逃逸而出 然后被由卡戎的重力所吸引After methane escapes from Pluto’s atmosphere, it’s caught by Charon’s gravity and then 然后聚集并冻结在了卫星的北极 这里也是卡戎卫星上面为数不多的collects and freezes on the moon’s north pole, one of the only places on Charon 温度低到可以常年冻结甲烷的地方之一cold enough to have frozen methane all year. 然后 来自太阳的紫外线会引起甲烷的化学反应Then, ultraviolet rays from the Sun cause a chemical reaction in the methane, 将其转变为索林 而这些红色的有机分子which turns it into tholins, those same reddish, organic molecules 让冥王星的天空变成了蓝色that make Pluto’s sky blue. 我们从来没有见过像卡戎一样的颜色We’ve never seen coloring like Charon’s before, 这貌似还要感谢冥王星and it looks like we can thank Pluto for that, too. 但这也归功于卡戎自身的一些很酷的特性But Charon can also take credit for some of its awesome features. 比如它拥有壮观的峡谷系统 长1800公里 深7.5公里Like its gigantic canyon system that’s 1800 kilometers long and up to 7.5 kilometers deep. 长度和深度都是科罗拉多大峡谷的四倍That’s four times as long and four times as deep as the Grand Canyon, 而卡戎的直径却比地球的十分之一还小even though Charon’s diameter is less than 10% of Earth’s. 峡谷可能延伸占据了卡戎外表面的很大一部分The canyon probably stretches around most of Charon’s surface, and there are also 在这个我们本以为平凡无趣的小卫星上 还有着大量的山脉plenty of mountains on what we thought was going to be a boring, little moon. 卡戎应该会继续保持这种奇怪的不均匀地质Charon might have ended up with that weirdly uneven geology because of a subsurface ocean 因为自从卫星形成以后 地下海洋已经冻结了几亿年了that froze a few hundred million years after the moon formed. 卡戎表面绝大部分都是冰 但是天文学家认为Most of Charon’s surface is made up of water ice, but astronomers think that right after 卡戎形成之初 可能还是足够热能够把地下坚冰融化的Charon formed, it might have been hot enough to melt some of the ice underground. 然后 随着时间的的推移 地下的海洋会冻结延展Then, over time, the underground ocean could have frozen, expanded, 然后在卡戎的表面造成巨大的断裂面and created that huge fracture in Charon’s surface. 我们不确定这是否真的发生了 但太阳系中出现了另一个海洋的可能We’re not positive that’s exactly what happened, but the possibility of another ocean 这真是让人感觉棒极了in the solar system is just plain awesome. 从冰火山的顶端到超级峡谷的底部So from the tip top of ice volcanoes to the bottom of super canyons, 新地平线号向我们展现了柯伊伯带比我们想象中的要更加精彩New Horizons has shown us that the Kuiper Belt is way more fascinating than we thought. 两年过去了 科学家们还有很多数据要分析And two years later, scientists still have plenty of data to analyze, 所以我们在以后还会了解到更多有关冥王星及其卫星的信息so we’ll be learning a lot more about Pluto and its moons in the future. 同时 新地平线号正沿着正轨去拜访柯伊伯带中叫做2014 MU69 的另一对象Meanwhile, New Horizons is on track to visit another object in the Kuiper Belt, 它被称为2014 MU69 预计到达时间为2019年的元旦called 2014 MU69, on New Year’s Day, 2019. 所以这个小型的宇宙飞船还在源源不断地向我们传授有关太阳系的知识So this little spacecraft isn’t done teaching us about the solar system yet. 当然我们也没有停下学习探索的脚步And neither are we! SciShow Space 的生存离不开我们在Patreon上的赞助者 比如我们的太空总统SciShow Space exists because of support from our Patreon patrons like SR Foxley, 老福克斯利our president of space! 如果你想当太空总统 或者想做些有趣的事情 比如参加我们每月的聚会If want to be president of space, or do fun stuff like join our monthly hangout, 去patreon.com/scishow上支持SciShow吧while helping to support SciShow, go to patreon.com/scishow. 谢谢你们!你们太棒了!Thanks! You guys are awesome!
  • 2021-10-30大脑里的GPS地图很快 确定你的血型Pretty soon, figuring out your blood type 将会像挤出一滴血在纸上那样容易might be as simple as squeezing a drop of blood onto a piece of paper. 上周 一个中国研究团队在《科学转化医学》杂志上发布了一篇报道Last week, a team of Chinese researchers reported in the journal Science Translational Medicine 称他们已经发明了一项新的测试方法that they’d come up with a new test 来鉴定你的血型是A型B型 AB型还是O型to see whether you have A, B, AB, or O blood, in 这个测试仅仅需要30秒in as few as 30 seconds. 因为你几乎不需要任何器材和时间Because you barely need any equipment or time 这项发明可以用于紧急输血 从而拯救生命this invention could help with emergency blood transfusions and save lives. 你的血型取决于你红细胞表层的抗原类型Your blood type is determined by what type of antigens decorate the outside of your red blood cells 抗原是免疫系统可以识别的糖和蛋白质它能够帮助抵御外来入侵Antigens are sugars and proteins that immune systems can recognize, to help defend against foreign invaders. 如果你有A型抗原 那么你就是A型血If you have the A antigen, you have A blood 如果你有B型抗原 那么你是B型血if you have the B antigen, you have B blood 如果两种抗原都有 你是AB型血两种都没有的话 你是O型血If have both, you’re AB, and have neither, you O 通常 血型测试需要两种不同的方法来确保其准确性Normally, blood testing involves two methods to make sure it’s right. 因为身体内输入错误的血可能会导致你的免疫系统紊乱Because picking the wrong blood for a transfusion can make your immune system go haywire 甚至可能要了你的命and like kill you 正向测试时 需要把血液样品和A或者B型抗体混合Forward testing checks for antigens, by mixing a blood sample with either A or B antibodies 如果你有A型抗原 它将会和A型抗体融合If you have A antigens, it’ll clump with A antibodies 而不会和B型抗体融合But not with B antibodies. 反向测试 也称后验测试 它的原理恰好相反Reverse, or back, testing, does the opposite. 反向测试将测试你血液中的液体成分即血浆的抗体It checks for what antibodies you have in the liquid part of your blood, called plasma 观察它是否能和已知的具有A或B型抗原的红细胞融合by seeing if it clumps with red blood cells known to have A or B antigens. 因此 反向测试是再次确认你正向测试结果的较好途径So, reverse testing is a great way to double-check your forward result. 但是 即使在效率最高的实验室里分离血液得到血浆But even the speediest labs have to centrifuge your blood to get the plasma 也至少需要10分钟and can’t do the test much faster than 10 minutes. 如果你在战场受了重伤If you’re seriously hurt on a battlefield 你没有器材或者时间去做那些事you don’t have the equipment or time for that 现在我们来看看试纸测试Enter the paper test. 它仍然是依据抗原抗体相融的原理It still relies on the fact that antibodies and antigens clump together 但是它添加了一种染色剂 试纸接触全部血液和只接触到血浆时 颜色是不同的but it uses a dye that changes color depending on whether it touches whole blood or just plasma 在正向测试把血液滴到测试条上后After you drip some blood on a forward test strip, 血液在到达染色剂的两侧之前它会流向试纸上干燥的A或B型抗体it runs into A and B antibodies that are dried onto the paper, before reaching two patches of dye. 如果你是A型血If you have type A blood, 红细胞会在A型抗体一侧凝结red blood cells will clump on the A antibody side 只有血浆会接触到染色剂 从而变成墨绿色so only the plasma will reach the dye, turning it a teal color 而B型血一侧没有任何东西凝结Nothing will clump on the B side 整个血样会接触染色剂 从而呈现棕色so the full sample will reach the dye and turn it brown. 因此 看是哪一侧变成墨绿色或者都变成墨绿色 或者都不变墨绿色So base on whether one, both, or neither side turns teal 你就可以知道自己的血型了you can figure out your blood type 至于二次测试是制作一个反向实验的测试条For double-checking, they made a strip with the reverse test on it too. 它有一个用于过滤血液的薄膜It has a thin membrane that filters the blood 所以在接触染色剂之前 无论血浆凝结与否 都能检测出其抗体的类型so the plasma can be checked for antibodies either forming clumps or not before touching the dye 研究人员在测试他们的发明时发现正向测试结果至多需要30秒When the researchers tested their invention, they got the forward result in 30 seconds 而反向测试至多需要2分钟且具有99.9%的精确度and the reverse one in 2 minutes, with 99.9% accuracy. 这种试纸测试现在还没被医生应用These paper tests aren’t being used by doctors yet 但是研究人员预期我们将会在1到2年内看到它们but the researchers hope we’ll be seeing them in the next year or two 部分科学家在研究血液而另一些在研究大脑中流动的血液Now, while some scientists are studying blood, others are studying blood flow in the brain. 在这周的《自然通讯》上Specifically, in a paper this week in Nature Communications 一个神经科学家团队发现了a team of neuroscientists discovered 在我们导航时 根据是否依靠GPS帮助的情况不同 某些大脑区域的活动方式会有所不同how certain brain regions act differently when we’re navigating with or without help from GPS. 研究人员通过让24名志愿者进行一场长达2小时的虚拟旅行The researchers had 24 volunteers take a 2 hour virtual tour through 来了解SOHO区 伦敦西区的一个时尚区域SOHO, a fashionable district in the West End of London, to learn the area 在第二天 对志愿者进行测试And the next day, the volunteers were quizzed 即怎样从各种A点到B点about how to get from various point As to point Bs 所有的都是虚拟的 科学家制作视频视频中有行走路线 在路线交叉点需要暂停行走Everything was still virtual: the scientists made videos of the walking routes, which paused at intersections. 他们会告知参与者要走哪条路或者让他们自行选择Then, they told participants which way to go, or asked them to choose 类似于谷歌地图的“选择你自己的冒险之路”kind of like a Google Maps Choose-Your-Own-Adventure. 与此同时 他们利用FRMI仪器监测志愿者的大脑While all this was happening, they monitored the volunteers’ brains with an fMRI machine 从而观察大脑的不同区域在不同的路线下是否会更活跃to see if different regions became more active with different kinds of routes. 研究发现 在以下情况下右海马体的后部是活跃的The researchers found that the back part of the right hippocampus was active 即人们主动辨认方向通过一个新的街道时when people who were actively navigating entered new streets, 尤其是在与终点的连接街道的数量发生变化的时候especially when there was a change in the number of connecting streets. 但是当志愿者不需要选择路线时But when the volunteers didn’t have to choose where to go next 类似于盲目遵循GPS指示他们的海马体几乎不活动kind of like blindly following GPS instructions – their hippocampi hardly lit up. 我们都知道海马体对空间记忆是很重要的We know the hippocampus is important for spatial memory 但我们还未确定它和导航之间的联系but we haven’t been so sure how it’s involved in navigation. 在这个实验中 科学家们认为In this experiment, the scientists think 海马体保存着所有可能的行走路线the hippocampus is keeping track of all the possible walking paths 用于帮助你模拟不同的路线to help you simulate different ways your journey could go 如果你只是被动的跟随指示而不利用你的海马体的话And if you’re just passively following instructions, and not using your hippocampus 你就不可能真的学会如何安排路线you might not actually be learning how to get around 这些结果符合之前针对伦敦出租车司机的一个测试These results fit with a previous experiment done with London taxi cab drivers 他们需要在10千米半径范围内通过约25000个伦敦的街道who need to pass a notoriously difficult test covering London’s 25,000 or so streets in a 10 kilometer radius. 研究员绘制出司机们开始测试前的大脑Researchers imaged the brains of drivers before they started training 三四年之后 会再测试一次and again three to four years later, after they took the test 通过测试的人比测试失败的人在他们的海马体后部有着更多的大脑组织And people who passed the test actually gained more brain tissue in the back of their hippocampus than those who failed. 因此 如果你好好锻炼你的大脑So, if you want to give your brain a good workout 尤其是你的右海马体especially you know, your right hippocampus 如果不是非GPS不可 就不要依靠它maybe pass on the GPS if you don’t definitely need it. 感谢观看这期的科学秀新闻Thanks for watching this episode of SciShow News 特别感谢这个月的太空部长福克斯利and thanks especially to this month’s President of Space SR Foxley 如果你也想当太空部长 帮助我们制作类似视频If you want be President of Space and help us keep making videos like this 可以去众筹网的科学秀频道you can go to patreon.com/scishow­ 不要忘记去油管科学秀订阅And don’t forget to go to youtube.com/scishow and subscribe!
  • 2021-10-26你能在骤降的电梯中存活吗?当电梯飞速穿过第15楼,此刻你正在So you’re in an elevator, just scrolling through your text messages as it zooms past 电梯内翻阅消息。the 15th floor. 突然间,电梯停了。And then, suddenly, the elevator stops. 这时你意识到自己悬在了半空中,而且真的很高。That’s when you realize that you’re suspended in midair, and you’re /really/ high up. 或许就在那一瞬,你在猜想电梯可能会随时Maybe that’s when you start to wonder: could your elevator start plummeting to the ground 急降到地面吧?at any second now? 如果电梯跌落了,你会存活吗?And if it falls, could you survive it? 好消息是,电梯几乎可确保不会骤降The good news is that the elevator almost definitely won’t fall. (电梯内)有包括并联绳索和急刹装置在内的许多安全设施,There are lots of safety features designed to prevent a plunge, including multiple ropes 用于阻止骤降and brakes. 若所有装置都停止工作了,也可通过将伤亡影响分散至全身这一方法And if absolutely everything fails, then there are ways to minimize the damage by distributing 将伤害降至最小。the impact all across your body. 但可不保证你会幸存哦。But there’s no guarantee that you’d survive. 在楼层不少的建筑里,电梯通常设为曳引电梯。In buildings of more than a few floors, the elevators are usually traction elevators. 通过将吊舱附着于金属绳或金属带上,借助电缆另一段的配重These work by attaching the car to metal ropes or belts and threading them through a motor, 机器得以线式穿过马达。with counterweights on the other end of the cable. 当引擎运动时,它缓慢牵引着电缆,带动吊舱或上或下地移动。When the motor is active, it slowly threads cable through, moving the car up or down. 如果马达出了问题,制动器会阻滞住吊舱。If something goes wrong with the motor, the brakes stop the car. 制动器有很多种,但在马达吊舱内常见的也就There are different kinds of brakes, but two common brakes are found in the motor and under 两种。the car. 一旦电力用尽,引擎中的制动器就会阻塞电缆。The brakes in the motor will make the cables jam and stop as soon as the power goes off. 同时,吊舱中的制动器也被用于侦查吊舱是否移动得Meanwhile, the brakes under the car are usually designed to detect if the car’s moving too 太快。fast. 若是太快了,制动器会沿着电梯轴释放金属楔子进入轨道。If it is, the brakes release a metal wedge into the rails along the elevator shaft. 楔子与轨道间的摩擦强大到足以慢慢将吊舱减速The friction between the wedge and the rail is strong enough to slow the car down and 并最终使其停下。eventually make it stop. 所以若马达突然停止工作,制动器将立即开始工作。So if the motor suddenly stopped working, the brakes would suddenly /start/ working. 难以想象所有马达和制动器都停止工作。It’s incredibly unlikely that both the motor /and/ all the brakes would fail. 但若真停止工作了,那配重器可就派上用场了。But if they did, that’s when the counterweights would come into play. 配重位于金属电缆的另一端,当它半满时,The counterweights are on the other side of the metal cable, and they’re normally about 大约等于电梯吊舱的重量。the weight of the elevator car when it’s half full. 最棒的假设情况是,电梯里的人数刚好In the best case scenario, you’d have the right number of people in the elevator so 与配重相平衡。所以若是你足够幸运,你可能that it exactly balances the counterweight — so if you’re really lucky, you might 完全没感到位移。not move at all. 所以若你单独在电梯里,你当然比配重要轻,And if you’re alone in the elevator, you might actually be lighter than the counterweights, 会开始向上移动,当吊舱冲入电梯车厢顶部时and start moving upward — though that can still be dangerous if the car is moving too 若它移动太快,那仍然是危险的。fast when it crashes into the top of the elevator shaft. 若是吊舱太满,它又会比配重更重,If it’s a full car, you’ll probably be heavier than the counterweights, and start 就会开始向下移动。moving down. 在任一情况下,配重都会平衡一些来自重力的加速度。In either situation, the counterweights balance out some of the acceleration from gravity. 然而当你到达电梯顶端或底部时,你就不会移动得By the time you reach the top or bottom of the elevator shaft, you won’t be moving 那么快了。as fast as you would otherwise. 但很多时候你依然能预想出相当危险的跌落,But a lot of the time you can still expect a pretty dangerous drop — especially if you’re 尤其是当你离电梯车厢尽头还很远时。a long way from the end of the elevator shaft. 也有可能是制动器罢工了,电缆崩塌了,There’s also the possibility that the brakes fail /and/ the cables snap, but there are 但那种情况几乎从未发生过。hardly any known cases of that happening. 多数电梯有很多电缆,每一根都设计得Most elevators have multiple cables, and every single cable is designed to be able to hold 足以支撑整个吊舱的重量。the weight of a full car. 事实上,通常都电梯拥有接近八根电缆,以及”12安全因素”原则,In fact, it’s pretty common for elevators to have up to /eight/ cables, and with a safety 就是说所有电缆加一起能承受住factor of 12 — meaning that all the cables together can hold a weight equivalent to 12 12倍于满载吊舱的重量。times the weight of a fully-loaded car. 所以即使一个电缆坏了,还有其他电缆能支撑住你。So even if a cable /did/ break, you’d have others holding you up. 在一个著名的案例中,一电梯的制动器坏了,电缆也崩塌了There’s one famous case where an elevator’s brakes failed and its cables snapped — it 这发生在1945年,一个飞行员无意将飞机在帝州建筑物内撞毁。happened in 1945, when a pilot accidentally crashed his plane into the Empire State Building. 据说一位名为贝蒂娄欧莉瓦的女士为出大楼进入了电梯。A woman named Betty Lou Oliver was told to get in an elevator to get out of the building. 但电缆因火损伤并崩塌了。But the cables were weakened by fire, and they snapped. 欧莉瓦和吊舱跌落了至少75层,直达地下室。Oliver and the car fell over 75 stories to the basement. 并且……欧莉瓦幸免于难。And … Oliver survived. 并不明确她是如何存活的,但一个可能性是吊舱移动得太快It’s not clear exactly /how/ she survived, but one possibility is that the car was moving 以至于吊舱刚好压迫下层空气到so fast that it compressed the air below to the point where it actually cushioned her 能缓冲她跌落冲力的程度。fall. 另一可能的解释是所有损坏的电缆堆积在轴的底层Another possible explanation is that all the broken cables piled up at the bottom of the 以此减轻了冲击力。shaft and softened the impact. 不管发生了什么,电梯基本上有套完善的安全网。Whatever happened, the elevator basically had a built-in safety net. 但回到你困于15层的话题上来,But back to your stuck elevator on the 15th floor. 你还是担心它可能会跌落,即使你明知那不太可能。You’re still worried that it might fall, even though you know that’s super unlikely. 若确实如此,你可能曾听说,如果你在着地前跳起,If it does, you might’ve heard that you’re more likely to survive if you jump just before 你就很可能存活。you hit the ground. 但那个说法存在两个主要的问题But there are two main problems with that idea. 首先,时机必须恰到好处,First, the timing has to be absolutely perfect, so that you’re jumping /exactly/ when the 那样你才可以精准地在在吊舱着地时起跳。car hits the ground. 其次,你需要有超强的跳跃力。And second, you’d need to have an exceptionally strong jump. 风险在于你动的真的很快,且你的跳跃没强大到Chances are you’re moving really, really, fast, and your jump won’t be powerful enough 使落地时你的速度与不跳时有明显区别。to make a difference in your speed when you hit the ground. 所以一个更可行的选择可能是将身体靠近地板。So a more realistic option might be to lay your body against the floor. 那看起来甚至有些费事Even that can be tricky. 若绳索坏了且你在自由坠落,你会有无重力感If the ropes are broken and you’re in free fall, you’ll feel weightless and it’ll 此时将自己拖到地板处是有些困难。be hard to pull yourself to the floor. 但你若成功了,冲击力会更平均地But if you manage to do that, then the impact will be distributed more evenly across your 分配到身体各部。body. 这并不保证你会存活,但它可能是你最棒的一博。It’s not a guarantee you’ll survive, but it might be your best shot. 感谢您观看这段科学秀,由我们的赞助商通过Thanks for watching this episode of SciShow, which was brought to you by our patrons on Patreon为您带来Patreon. 若你想赞助支持这一节目,敬请登录patreon.com/scishowIf you want to help support this show, just go to patreon.com/scishow. 也别忘了上youtube.com/scishow订阅我们的节目哦!And don’t forget to go to youtube.com/scishow and subscribe!
  • 2021-10-26怎样把焦虑转变为动力?感谢CuriosityStream对本集的支持!Thanks for CuriosityStream for supportingthis episode! 访问CuriosityStream.com/Psych了解更多Go to CuriosityStream.com/Psych to learn more. [背景音乐][♪ INTRO ] 想象一下:你正在后台为音乐会做准备 你已为之练习了四周Picture this: you’re backstage getting ready for a concert you’ve been practicing for four weeks. 你看上去很紧张 但你后台的朋友们非常开心 兴奋并告诉你说You’re nervous as all get out, while your friends backstage is smiling and excited.and they tell you “你并不紧张 你只是也很兴奋”“You’re not nervous,you’re just excited too!” 他们所说的话可能会让你有点恼火Depending on how they say it, you might be kind of annoyed. 因为你知道自己的感受Like, you know how you feel. 而另一方面 也许你已经为这场表演兴奋了很久On the other hand, maybe you’ve been excited about this show for a while. 而且尝试将你的感受引导成这样的情绪可能会有帮助And trying to channel your energy into that feeling now could actually work. 这就是所谓的“情感再评价”It’s called emotional reappraisal. 其基本概念是 你的情绪是你的生理反应和当前想法的一个综合体The basic idea is that your emotions are really a combination of your physiology and what you’re thinking. 所以 改变想法能真正转变你所经历的情绪So,changing what you think can literally change the emotion you experience. 自心理学开创以来For as long as psychology’s been a thing, 什么是情绪的争论就从未停止过there’s been some debate about what an emotion is, 且该情绪与其他想法和经历有怎样的不同呢and how it’s different from other kinds of thoughts and experiences. 但近期 心理学家确信至少存在两种主要的组成部分:But lately psychologists are pretty sure thatthere are at least two major components: 你身体所具有的下意识的反应some kind of automatic reaction your body is having, 以及你对那种反应给出的解释plus your interpretation of why you’re reacting that way. 就像看到一辆车快速开来时 你的心跳加快一样Like if your heart starts racing as soon as you see a car speeding down the road, 你可能会因害怕被撞上而感到恐惧you probably experience that as the fear of possibly being hit, 因为你知道这辆车能使你处于危险的境地because you know the car could be dangerous. 接下来的部分叫做“评估” 这是你对自己为何This latter part is called”appraisal,” andit’s basically your inferences 有这样感受的基本判断about why your body feels the way it does. 尽管如此 但倘若你能转换这种评估If you can change the appraisal, though, 你就可能改变自己的情绪体验you might be able to change your emotional experience. 就像那辆车出现在赛场上Like if that car’s on a race track, 也许你仅仅会对比赛感到兴奋maybe you’re just excited about the race. 有项研究为证实这个结论 招募了90人参与实验One study demonstrated this by recruiting 90 men to participate in an experiment 当他们站在桥上时——在悬空摇晃的桥或稳固的桥上while on a footbridge — either a shaky suspension bridge or a stable one. 研究者们向参与者展示一张图片The researchers showed the participants a picture 并要他们讲一个关于这张图片的故事and asked them to tell a story about it. 随后 他们给参与者留下了自己的联系方式Then they offered the participant their phone number, 并称他们能告诉参与者更多研究信息 如果参与者稍后给他们打电话的话saying they could tell them more about the study if they called later. 当这些参与者—全是直男When these participants — who were all straight men — 在一座摇晃并且令人恐惧的桥上时were on the shaky, scary bridge, 他们讲的故事有更多性感和浪漫的成分the stories they told had more sexual and romantic content. 并且之后他们更可能打给研究者And they were more likely to call the research later… 如果研究者是女性的话if it was a woman. 但如果参与者站在稳固的桥上 或研究人员也是男性的话But this didn’t happen if they were on the sturdy bridge — 这种情况就不会发生or if the researcher was also a man. 这些心理学家指出 在摇晃的桥上What these psychologists figured was happening was that on the shaky bridge, 人们会产生恐惧反应—比如心跳加速并大量出汗people were having a fear reaction — things like heart racing and sweating more. 但当研究人员是女性时But when the researcher was a woman, 他们会将其理解为性吸引they interpreted it as sexual attraction, 从而想到浪漫故事并且更可能打电话leading to the romantic stories and the increased phone calls. 人们在摇晃的桥上时 常表现出相同的生理反应People had roughly the same physiological reaction on the shaky bridge 大多数报道都是恐惧多一些most reported being more fearful. 但当提供给他们对情形的另一种解释时 他们也接受了But when given a situation that provided an alternate explanation, they took it. 我们曾经在考虑错误评估之前提到过这项实验We’ve mentioned this study before in the context of misattribution 人们有时会错把恐惧当作爱where people can sometimes mistake fear for love. 但是重新评估时But with reappraisal, 你可以利用情绪的这种怪异特点 特意去改变对情感的解读you can use this quirk of emotions to change your interpretation of your feelings on purpose. 当140名学生被告知 他们必须发表一篇有说服力的演讲When 140 students were told that they had to deliver a persuasive speech 并交给委员会进行记录和评判时 显然他们会变得焦虑that would be recorded and judged by a committee, they understandably started to get nervous. 但随后 一半人被告知要特意暗示自己很兴奋But then, half the group was told to reappraise their reaction 来重新评估他们的感受by specifically telling themselves that they felt excited- 同时另一半人被告知他们感到焦虑the other half was told to say they felt anxious. 尽管这并没有改变多少学生对演讲的焦虑程度Although that didn’t change how much anxiety the students reported about the speech, 但后来那些被告知很兴奋的学生表示those who were told to say they were excited 他们确实对演讲感到兴奋later said they did actually feel excited by it. 不过这有一个非常酷的部分:But here’s the really cool part: 委员会是完全真实的 并且他们不知道每个演讲者属于哪一组the committee was totally real, and didn’t know what group each of the speakers were in. 当他们评价那些被告知感到兴奋的参与者时 认为他们更有说服力 也更有竞争力And they rated participants in the group that told themselves they were excited as more persuasive, competent, 且相对于被告知感到焦虑的那组 他们更加自信and confident than the group told to appraise their feelings as anxiety. 所以 当你重新评估自己的情绪时So while you’re reappraising your emotions, 你并不是在否认自己的感受you’re not denying your feelings — 研究中的参与者仍会感到紧张the people in the study still felt nervous. 但观点的改变却能在其他方面帮助他们but the change in perspective helped them in other ways 包括情感以及表现both emotionally, and in their performance. 心理学家认为这样可行Psychologists think this works 因为你对事物的情感反应有两种不同的途径because you have two different pathways for how you react emotionally to things. 这两种途径都从丘脑开始—这部分大脑 能监控你的感觉神经输入Both of these paths start with the thalamus — that’s a part of the brain that monitors all your sensory input. 倘若某件事真的非常不正常If something’s really out of place, 丘脑会发出信号要你立即采取行动it sends signals that you should spring into action. 一种信号传入杏仁核—这是快速通路One signal goes to the amygdala —the fast path 另一种进入大脑皮层 这是慢速通路and another to the cortex — the slower path. 杏仁核开始会恐惧的反应The amygdala starts a fear reaction, 这是它工作中的一个重要部分which is a big part of its job in general. 同时大脑皮层需要确定 这是否真是需要害怕的东西Meanwhile, cortex needs to process whether it’s really something to be scared of, 随后它将信号传回杏仁核 “冷静点 兄弟”and then it can send a signal back to the amygdala to, you know, chill out, man. 这种解释容易理解的前提 是用核磁共振成像This explanation seems to make sense when we actually look at the brains of people as 观察人的大脑 重新评估情绪they reappraise emotions, using fMRI. 当人们看到消极的场景时When people were showed negative scenes, 他们的杏仁核 比引发中性情绪的场景时更活跃their amygdala activated more than with neutral scenes. 但当人们被要求用更愉快的故事来重新解读这些场景时But when they were asked to reinterpret those scenes with a better story 他们杏仁核的兴奋性再次降低their amygdala activation went back down. 与此同时 他们的前额皮质中And at the same time, parts of their prefrontal cortex, 负责掌控高层次推理的部分which is in charge of higher-level reasoning, 通过重新评估而被激活were activated by that reappraisal. 值得注意的是 并非每个人都擅长这种做法It’s good to note that not everyone is equally good at doing this. 研究人员把更擅长重新评估情绪的人称为具有“情感灵活性”Some people who are better at reappraising are referred to as having”affective flexibility.” 这意味着他们在避免消极反应以及关注积极情感方面做得更好This means they’re better at avoiding negative responses and focusing on the positive, 这也可以作为整体心理健康的一个标志and might also be a sign of better mental healthoverall. 如果你能这样做 重新评估也许有助于使你的情绪变得更加积极But when you can, reappraising seems to help make your mood more positive. 由于重新评估有助于把压力大的事情变得轻松些And since reappraising can help make stressful things feel less stressful, 那么这会是一个非常有用的帮你冷静的工具it’s pretty useful tool to have to help you chill out. 感谢观看本期科学秀心理学thanks for watching this episode of scishow psychology 如果你想学习更多心理学知识 或其他诸如历史或科学的话题if you want to learn more about psychology or about psychology — or other topics in fields like history or science- 我们为你找了一些你可能会喜欢的视频we think we’ve found some videos you might enjoy. 而这也是Curiositystream给你带来这集节目的原因And that’s why this episode is brought to you by CuriosityStream. Curiositystream是一个订阅电台 并提供超过2000多部CuriosityStream is a subscription streaming service that offers over 2000 documentaries 由世界上最好的电影制作人制作的纪录片和原创视频and non­fiction titles from some of the world’s best filmmakers, including exclusive originals. 他们提供有关自然历史和科技They have videos on nature, history,technology- 以及社会和生活方式等方面的视频even society and lifestyles — 而这也是我们如此喜欢他们的原因之一which is one of the reasons we like them so much. 这里有很多可以学习的东西There’s so much to learn! 比如有个叫做Breakthrough的节目Like there’s a show called Breakthrough 报道一些领域的最新发展that covers some of the recent developmentsin multiple fields, 包括心理学和解剖学including psychology andastronomy. 因此如果你想要学习一些 很酷的事情 比如卡西尼土星任务So you get to learn a little bit about a bunch of cool things, including the Cassini mission to Saturn 和老年痴呆症研究的新进展and new developments in Alzheimer’sresearch. 你只需每月花费2.99$ 就可无限量观看这些视频You can get unlimited access to content like this starting at $ 2.99 a month. 并且为了特别感谢心理科学秀的观众们And as a special thanks to our SciShow Psych audience, 前30天完全免费you can get the first 30 days for free! 你只需要curiositystream.com/psych 注册You just have to sign up at curiositystream.com/psych 并在注册过程中使用促销代码“psych” 即可使用and use the promo code “psych” during the sign-up process. 背景音乐[♪OUTRO ]
  • 2021-10-26神奇的蛇!你愿意和我做一个关于对和错的游戏吗?How would you like to play a game of True or False? 我和吱吱想出一个有趣的游戏:猜一下我们所喜爱的动物——蛇Squeaks and I came up with a really fun game where you guess what’s true and what’s 所具有的某些特征或不具有哪些特征not about one of our favorite kinds of animals — 是正确还是错误!— snakes! 蛇是一种非常有趣的动物 而且有很多不同的种类!Snakes are super interesting, and there are lots of different kinds! 据科学家研究地球上有超过3500多种蛇!Scientists think there are more than 3,500 different types of snakes in the world! 最小的蛇差不多和一根意大利面一样细而且还可以很惬意地盘The smallest is about as thin as a piece of spaghetti, and can curl up comfortably on 在一个25分的硬币上a quarter. 但是另一种名为蟒蛇的蛇 能够长到十米长——But another kind, called a python, can grow to be about ten meters long — which is just 就比校园车短了一点!a bit shorter than a school bus! 一些蛇色彩鲜艳 但是另外一些蛇与它们生活的环境颜色相应Some snakes are brightly colored, while others blend in really well to their environments. 但有几件 许多人包括小孩子们都认为的关于蛇的事情But there are a few things that a lot of people — including kids! — tend to think about 它们却并不正确snakes, and they’re not true! 所以 我们想出了这个很棒的游戏 你能学习到很多关于这些奇妙的动物So, we came up with this awesome game, so you can learn the facts about these amazing 的特征!animals! 我将会问吱吱一些关于蛇的问题 你们可以和吱吱猜一猜这些问题的对错!I’ll say something about snakes, and you and Squeaks can guess if it’s true or false! 准备好了吗?Ready? 好 让我们开始!Alright! 第一个问题!Number one! 蛇是黏滑而且湿软的Snakes are slimy and squishy. 对还是错?True or false? (吱吱吱吱)(Squeaks squeaks) 对 吱吱 那是错误的!Right, Squeaks, that’s false! 所有的蛇都属于动物的一个物种——爬行动物All snakes belong to a group of animals called reptiles. 像很多爬行动物一样 蛇拥有遍布全身的鳞片的皮肤来保护它们自己Like all reptiles, snakes have skin that’s covered with scales to help protect them. 触摸一下你的手指甲Touch your fingernail. 是什么感觉?How does it feel? 蛇的鳞片触摸起来就是这种感觉!Snake scales feel a lot like that! 只是因为蛇的鳞片是由类似于你的手指甲和脚趾甲的材料制成的!That’s because scales are made of the same stuff as your fingernails and toenails! 所以蛇鳞摸起来很硬 还有 大多数时候十分光滑。So scales feel hard, and, most of the time, pretty smooth. 意思就是抚摸一条蛇一完全感受不会感受到黏滑!Which means that a snake doesn’t feel slimy at all! 会感觉干燥!It feels dry! 但是蛇是湿软的 像蠕虫那样吗?But are snakes squishy, like a worm? 并不是!Nope! 所有的爬行动物 包括蛇 都有一些有其它骨骼的骨架All reptiles, including snakes, also have something else—a skeleton made of bones. 实际上 一条蛇的骨骼有很多我们骨骼的相同的部分In fact, a snake’s skeleton has a lot of the same parts that our skeletons have. 你能够伸手摸到你背部的中央吗?Can you reach around and touch the middle of your back? 如果你可以的话 接下来你能感觉到你背上If you can, then you should be able to feel hard bumps from the top of your neck all the 一路下来坚硬的突起物way down. 这些突起物是由骨骼组成的你的脊梁These bumps are caused by the bones that make up your backbone. 你身体里的肌肉和脊梁相联系 还帮助你做各种各样的事情Muscles inside your body connect to your backbone, and help you do all kinds of things, like 像是站立 弯腰 坐下stand up, bend over, and sit down. 一条蛇也拥有脊梁A snake has a backbone, too! 而且蛇的脊梁和你的脊梁有着相同的作用And it does the same job as your backbone. 它的作用就是帮助蛇的肌肉活动It works with a snake’s muscles to help it move. 蛇行走的路径很酷——而且这种步伐的还有一个很有趣的名字:The way a snake moves is really cool—and it has a name that’s kind of fun to say: 蛇行slithering. 所以 拥有脊梁意味着蛇不是像蠕虫一样柔软且黏湿的So, having a backbone means that snakes aren’t soft and squishy like worms. 即使蠕虫和蛇拥有着看起来相同的外形 但是Even though worms and snakes have a shape that looks kind of the same, they’re not 它们不是同一种动物the same kind of animal. 蠕虫没有骨骼 或者脊梁Worms don’t have a skeleton, or a backbone. 所以蠕虫不能滑行 它们能够蠕动 或者爬行So worms don’t slither, they wriggle, or crawl. 好了 让我们开始游戏里的第二个问题:蛇会袭击并且追逐人类Ok let’s move on to question Number Two in our game: Snakes attack and chase people. 对还是错?True or false? (吱吱吱吱)(Squeaks squeaks) 你是正确的 吱吱!You’re right, Squeaks! 这句话也是错误的That’s false, too 你可能听别人说过蛇是具有攻击性的 这意味着You might have heared people say that snakes are aggressive, which means they’ll attack 它们会攻击和追逐人类or chase people. 但这不是真的But that’s not true. 蛇在一般情况下是很害羞的 当有人在附近时Snakes are usually pretty shy, and most of the time, they’ll slither away to hide when 大多数时候它们滑行着隐藏自己people are around. 但是它们害怕没有地方可以隐藏的时候会咬人But they will bite if they are afraid or if they can’t get away to hide. 所以 如果你看到一条蛇 你不需要逃跑So, if you do see a snake, you don’t need to run away. 你只需要让它们单独待着 给它们足够的空间But you should leave them alone, and give them lots of space. 好 让我们继续下一个问题Ok, let’s do one more question. 第三个问题:蛇是很重要的一种动物Number Three: Snakes are important. 对还是错?True or false? 答案当然是正确无疑了!This one is definitely true! 蛇是非常重要的一种动物Snakes are very important animals. 蛇吃其他动物 在它所吃的这些动物里Snakes eat other animals, and many of those animals that snakes eat are ones that can 有一些动物能制造出很多问题sometimes cause problems. 蛇可能吃一些小昆虫 像是 像是蚊子……Snakes might eat baby insects like, like mosquitos… ……或者蛞蝓,这些虫子会危害我们花园生长的花朵和蔬菜………or slugs, that can eat the flowers and vegetables that grow in our gardens… 它们甚至吃老鼠 大老鼠 还有其他的一些携带疾病的动物They can even eat mice, rats, and other small animals that sometimes carry disease. 抱歉吱吱!Sorry Squeaks! 但是你是安全的!But you’re safe! 蛇不吃机器老鼠!Snakes don’t eat robot rats! 现在 想像如果蛇不吃这些动物的话会发生什么Now, imagine what might happen if snakes weren’t around to eat some of these animals. 它们会越来越多 而且制造出来的问题会变得更大!There would be more and more of them…and the problems they cause would get bigger too! 所以蛇能够对自然环境起到一个平衡作用So having snakes around helps keep an environment in balance. 自然环境保持平衡是对所有生物都有好处的——包括对人类!And an environment that’s in balance is good for all living things—including people! 所以 如果当你足够幸运在出去的时候看到一条蛇So, if you’re lucky enough to see a snake when you’re out and ——你不必惧怕它about— you don’t need to be afraid of it. 实际上 你可能想要向它招手 并且和它说一句“谢谢你”!In fact, you might want to give it a wave and tell it, “thank you”! 一如既往 谢谢你 我的孩子 加入scishow!And thank you, as always, for joining me on SciShow Kids! 在城堡你对我们还有什么问题吗?Do you have a question for us here at the Fort? 寻求大人帮助你在下面留下评论 或者发送Email到Kids@scishow.com!Ask a grownup to help you to leave a comment down below, or send us an email to Kids@scishow.com! 谢谢 下一次我们会在城堡再会!Thanks, and we’ll see you next time here at the Fort!
  • 2021-10-26心脏细胞会转变成骨细胞?像钙和磷酸盐这样的矿物质使你的骨骼保持坚硬Minerals like calcium and phosphate keep your bones tough and rigid, so your limbs can be 这样你的四肢才能正常地活动你的躯体才不至于成为一堆软乎乎的组织attached properly, and your body’s not just a squishy mess of tissue. 但有时矿物质能够在意料之外的地方起作用But sometimes minerals can build up where they’re not supposed to. 事实上 心脏病发作后你的部分心肌组织能有效的转化为骨In fact, after a heart attack, some of your heart tissue could effectively turn into bone. 这可能听起来像是一种超强突变但实际上这相当危险This might sound kind of like a mutant superpower, but it’s actually really dangerous, and 并且曾经困扰了科学家一段时间has perplexed scientists for a while. 但发表在Cell Stem Cell杂志上的最新研究表明But a new study published in the journal Cell Stem Cell suggests that these bony calcium 这些骨钙沉积仅仅是心脏试图治愈自身的不良副产物deposits are just an unfortunate byproduct of the heart trying to heal itself. 心肌组织和骨组织具有完全不同的功能 这并不奇怪It’s no surprise that heart tissue and bone tissue have really different jobs. 心肌必须灵活 以一定的节律跳动从而保持血液循环Heart muscle has to be flexible and beat in a rhythm to keep your blood circulating. 你的心跳受到心肌细胞中传递的电信号的控制Your heartbeat is controlled by electrical signals that spread through the muscle cells 这些心肌细胞构成不同的心脏室that make up different heart chambers. 因此当心脏组织变得僵硬和矿化时它也就不能执行这些电信号了So when heart tissue turns all stiff and mineralized, it can’t conduct those signals as well, 心脏不能保持平稳的心跳这种情况叫做心肌梗死and your heart can’t keep that smooth, steady beat – a condition called heart block. 并且这些钙沉积物一旦形成目前没有医疗手段能够分解And there’s currently no medical treatment to break down these calcium deposits if they 它们form. 这些类骨组织会在心脏病发作后形成它们会阻碍血液流动This bone-like tissue can form after a heart attack, where blood flow gets blocked, so 因此细胞会缺氧并开始坏死the cells get deprived of oxygen and start to die. 我们知道 心脏受伤时会自我修复We know that the heart can kind of repair itself when it gets injured. 事实上 在更早的文献中这个团队的研究显示 一些心脏细胞In fact, in an earlier paper, this team of researchers showed that some heart cells can 甚至能够转而承担修补工作even switch jobs to try and patch things up. 通常 所有成熟细胞都有其特定功能并且一直保持这样See, usually, all mature cells take on a specific function and stay that way forever. 但罕见地 在接收到来自身体的正确信号时某些细胞可以改变形态But rarely, with the right signal from the body, certain cells can change forms. 这种情况下 这些“变节者”被称为心脏成纤维细胞 它是一种连接细胞In this case, the turncoats are called cardiac fibroblasts, a type of connective cell, which 能够在机体受伤之后成为血管细胞can become blood vessel cells after an injury. 在本周发表的研究中这些研究者发现心脏成纤维细胞And in the study published this week, these researchers found that cardiac fibroblasts 也能够表现成骨细胞的特性成骨细胞负责在骨骼中can also become cells that act just like osteoblasts, the cells responsible for depositing minerals 储存矿物质in your bones. 为了弄清楚 他们从心脏钙化的老鼠身上获取成纤维细胞To figure this out, they took heart fibroblasts from mice with calcified hearts and put them 然后放到正常老鼠心脏里in healthy mice hearts. 他们观察到这些类成骨细胞开始储存钙质They observed that these osteoblast-like cells started depositing calcium, and mineralizing 并矿化其他细胞other cells. 他们仍然不能完全确定心脏细胞为何会大量释放矿物质They’re still not completely sure why heart cells would start spewing out minerals, but 但那可能是一个意外it’s probably an accident. 可能成纤维细胞试图通过转变功能来变的更有用 但它们搞砸了Maybe the fibroblasts are trying to switch jobs one way to be helpful, they mess up, 走上了一条不同的发展道路and go down a different developmental path. 研究者希望 通过理解心脏细胞的犯错机制The researchers hope that by understanding how heart cells can make this mistake, they’ll 他们能够开发出阻断病人体内这种钙沉积的药物be able to develop drugs that block this sort of calcium buildup in patients. 许多科学家在研究很不起眼但是可能在人体中Lots of scientists are researching really 出错的过程 但是还有很多科学家关注的是全球的small things that can go wrong in human bodies, but plenty are also looking at planet-wide 问题issues. 比如 一些鱼类种群数量由于商业捕鱼和气候变化的原因For example, some fish populations are plummeting because of things like commercial fishing 而骤降and climate change. 并不是你把头伸到水下数数就能核实And it’s not like you can just stick your head underwater and count them to check on 危害的程度the damage. 因此 在一项新研究中一个丹麦的研究团队认为 一苏打水瓶的海水So, in a new paper, a team of Danish researchers think a soda bottle full of seawater might 可能能够告诉我们 海里有多少鱼 是什么种类的have the power to tell us how many and what kinds of fish are in the ocean. 监视鱼类种群数量的一种方法是拖网作业即在海底撒一张大网One strategy to keep tabs on fish populations is trawling, or dragging a big net across 看看能捞上来什么the seafloor and seeing what you scoop up. 但是这种方法存在问题:不是所有的海底都平坦到适合撒网But it has its problems: only part of the ocean floor is flat enough to drag a net across, 一些大型的动物能轻易地避开网这种方法太具侵略性some bigger animals can easily avoid the nets, it’s pretty invasive, and it’s not all 并且没有那么快that fast. 研究者也可以了解渔业公司捕到的鱼数量Researchers can also ask commercial fishing companies how much they’ve caught, and try 以此来推断鱼类种群的数量to estimate fish populations that way. 但现在是二十一世纪了如今我们有更酷的科学玩具But this is the twenty-first century, and we have cool sciencey toys now, like quick, 比如快速 廉价 精确的DNA测序cheap, accurate DNA sequencing. 鱼类在水中会一直脱落DNA就像我们人类到哪都会留下Fish shed DNA in the water all the time, just like we humans leave bits and pieces of ourselves 我们自身的皮屑毛发一样wherever we go. 所以一个丹麦的研究者团队认为他们可以从水中取得一些环境DNA 或eDNASo instead of scooping up the fish, a team of Danish researchers figured they could just 来取代捕鱼 然后将得到的DNA和已有的scoop up a bunch of environmental DNA, or eDNA, from the water, and match it to known 组织样本和序列进行比对tissue samples and sequences. 他们同时进行了拖网作业研究和这个eDNA研究They ran a traditional trawling study side-by-side with this eDNA study, pulling up two liters 在每个撒网的地方取两升水样–一瓶苏打水的量of water – a soda-bottle sized amount – everywhere they dropped a net. 在大多数情况下eDNA能够告诉他们在那片海里有哪些And, for the most part, the eDNA was able to tell them what was in that part of the 动物ocean. eDNA测序确实漏掉了一些拖网作业捕到的稀有鱼 说明两升水eDNA sequencing did miss some rare fish that trawling caught, suggesting that two liters 里这些鱼DNA的含量不够多of water just didn’t have enough of their DNA in it. 另外 科学家仍然在研究如何用DNA的含量估计Plus, the scientists are still figuring out how the amount of DNA can be used to estimate 海里鱼的数量the actual number of fish in the water. 但对其中一个物种 格陵兰鲨鱼来说eDNA方法实际上已经But in the case of one species, the Greenland shark, the eDNA method may actually have done 比拖网作业得到了更好的结果a better job than trawling. 研究者说格陵兰鲨鱼大到能够避开拖网The researchers say that Greenland sharks are big enough to avoid trawling nets. 但这个问题不适用于它们的DNA 所以eDNA方法可能提供了更好的方法估计它们的But this issue doesn’t apply to their DNA, so it might provide a better estimate of their 数量numbers. 主要是因为eDNA测序对环境的破坏性比拖网作业小得多 这些科学家认为Mostly, because eDNA sequencing is much less invasive than trawling, these scientists think 这是未来鱼类研究一个很有前途的方向即使它仍需改善it’s a promising option for future fish studies, even though it still needs some refining. 谢谢观看由我们的President of Space带来的本期科学秀Thanks for watching this episode of SciShow News, brought to you by our President of Space, 你一定猜到了you guessed it…. SR FoxleySR Foxley! 谢谢SRThanks SR! 如果你想赞助本节目可以去patreon.com/scishowAnd if you want to help support this show, you can go to patreon.com/scishow. 别忘了去youtube.com/scishow订阅我们And don’t forget to go to youtube.com/scishow and subscribe!
  • 2021-10-26记忆的工作原理Thank you to brilliant.org for supporting PBS Digital Studios.感谢brilliant.org对PBS数字工作室的支持 Sherlock Holmes, the legendary detective传说中的侦探夏洛克•福尔摩斯 had a theory that the brain is like an attic曾提出一个理论 认为大脑就像一间阁楼 where a person can only store a limited amount of memories.人们只能在里面储存有限的记忆 Dr. Watson once told him that the Earth travels around the sun,华生医生曾告诉他 地球绕着太阳转 duh, to which Holmes replied,对此 福尔摩斯回答说 “Now that I do know it, I shall do my best to forget it.”“既然我已经知道了 就会尽力忘记它” Holmes figured,福尔摩斯认为 clutter your attic with random facts and trivia,如果你的阁楼里尽是凌乱的琐事 and you won’t have room for the things that matter,就没有空间留给重要的事 like identifying the tiny differences between lethal poisons.比如辨别不同致命毒药之间的细微差别 Was Holmes right?福尔摩斯说的对吗? Is our memory limited, like the storage capacity of a computer?我们的记忆像电脑容量一样有限? Or is our memory unlimited?还是无限呢? And if we did have perfect memory,如果我们真的拥有完美的记忆力 what would life be like if you never forgot anything?如果你从不忘记任何事 那么生活会是什么样? [OPEN][开始] The animated film Inside Out depicted memories动画电影《头脑特工队》将记忆描绘为 as glowing spheres stacked in the brain,堆积在大脑中的发光球体 like books in a library.就像图书馆里的书一样 But the reality is a little more complicated.但事实要更复杂一些 There is no one place in the brain大脑中没有任何一个地方 that serves as our memory bank.可以做我们的记忆库 Instead, individual memories are scattered all over the brain.相反 记忆散落在大脑各处 Many brain cells, in several different regions,位于不同区域的许多脑细胞 work together to make one memory.共同形成一个记忆 For example, a memory of eating grandma’s apple pie might involve例如 吃祖母做的苹果派的记忆可能包含很多脑细胞 some brain cells to help you remember what the pie looked like,一些帮你记住派的样子 others to remember the smell of the cinnamon,一些用来记住肉桂的气味 and even cells to remember the delicious taste甚至还有一些用来记住美好的味道 just name a few.这里只举几个例子 In reality, though, a memory isn’t a physical thing然而 事实上 记忆并不是 that we can find in any given brain cell.我们在任何脑细胞中都能找到的物质 It’s an action, not an object.它是一种行为 而不是一个物体 Think of baseball fans doing “the wave”:想想棒球迷们摆“人浪” no single fan IS the wave,一个人形不成浪 the magic only happens when all the fans are together,只有当所有球迷一起按一定顺序摆动时 doing their thing in a specific order.才会出现奇迹 In the same way, a memory only happens同样 只有当多个相连的神经元 when many connected neurons fire in a specific pattern.以特定方式放电时 才会产生记忆 Because the same cells can fire in many unique patterns,由于相同细胞能以多种独特的模式放电 one group of neurons can encode multiple memories.一组神经元可以编码多个记忆 This increases the memory storage capacity of the brain.这增加了大脑储存记忆的容量 Buried deep in the middle of the brain在大脑中部的深处 we find a group of cells shaped like a seahorse,我们发现了一组形状像海马一样的细胞 which is why 18th century scientists named this bit the ‘hippocampus.’因此 十八世纪的科学家们将其命名为“海马体” Without your seahorse, you might never remember.没有海马体 你可能永远不会有记忆 We owe a lot of our understanding of memories to one famous patient,我们对记忆的很多认识源于一个著名的病人 known for years only by his initials, H.M..多年来 我们只知道他名字的缩写是 H.M. In 1953, H.M. underwent a surgery for epilepsy,1953年 H.M.做了一次癫痫手术 which demolished most of his hippocampus.手术损伤了他大部分的海马体 For the rest of his life,此后余生 he exhibited a severe type of amnesia他患上了严重的健忘症 where he was unable to form new memories of facts or events.无法再形成对事实和事件的新记忆 But, he was still able to remember things但他仍然记得 he had learned before the surgery.手术之前的事 They showed us the hippocampus is a key to making memories,这表明 海马体是制造记忆的关键 but it isn’t where memories are stored.但不是储存记忆的地方 So how do experiences become memories?那么 经历是如何变成记忆的呢? If we look inside the brain of a mouse in a maze,如果我们观察身处迷宫中的老鼠的大脑 we could draw a kind of map,我们可以画出一张地图 showing which brain cells are active显示老鼠在经历事情时 as the mouse experiences something.哪些脑细胞是活跃的 Later, we would see the mouse’s brain cells随后我们看到 老鼠的脑细胞 firing in the same patterns,以同样的方式放电 replaying the experience in fast forward,快速 一次次 来来回回地 over and over, backwards and forwards回放这次经历 to make the connections between cells stronger.以加强细胞间的联系 This is called consolidation and it’s how animals, including humans,这被称为巩固 是动物 包括人类 commit new memories to long-term storage.将新记忆长期储存起来的方式 Days or weeks later,几天或几周后 a smell might trigger the same pattern of cells firing in the mouse’s brain,一种气味可能会使老鼠大脑中相同的细胞放电 a recall of the maze memories, 回溯关于迷宫的记忆 just like smelling cinnamon might trigger memories of grandma for you.就像闻到肉桂味会让你想到你祖母一样 But the brain’s way of creating memories isn’t foolproof.但大脑创造记忆的方式并不是万全的 Sometimes, our mental replay of something we only imagined有时 我们大脑回放只是想象出的事物时 can feel as vivid as a real experience.会像真实经历一样生动 If you picture all the sights, smells, and sounds of a crime scene如果你根据某人的描述去想象 from someone’s description,犯罪现场的场景 气味和声音 you activate similar brain networks你就会激活大脑中类似的细胞网络 as if you had really been there.像你真的在犯罪现场一样 The more you replay the scene in your mind,你越在脑海中重复这一场景 the more it feels like a real memory.就越觉得那是真实的记忆 That’s why a detective who asks leading questions这就是为什么一个提出引导性问题的侦探 can inadvertently plant a false memory in a witness.会在不经意间给证人植入错误的记忆 We’re able to remember a lot, but we forget even more.我们能记住很多东西 但忘记的更多 Some forgetting just happens,有些就是忘记了 but our brains also forget on purpose.但我们的大脑也会有意去忘记 We have at least three different ways of forgetting.我们至少有三种不同的遗忘方式 The first is what happens when a memory fades over time,第一种是记忆随着时间慢慢淡去 so-called “passive oblivescence”即所谓的“被动遗忘” (a term you will probably forget).(一个你可能会忘记的概念) This may happen because这可能是因为 the connections between brain cells gradually weaken over time;脑细胞间的连接会随时间流逝而减弱 or perhaps the memory is still there,或者可能这个记忆仍然在 but you might lose the triggers–sights, sounds, smells–you need to retrieve it.但你失去了能激发它的场景 声音 气味 Another idea says memories could theoretically last forever,另一种观点认为 理论上讲记忆可以永存 when the same neurons get used in other memories,但当相同的神经元被用于其他记忆中时 this “interference” disrupts the original memory.这种“干扰”会破坏原始记忆 This slow fade type of forgetting happens to all of us, eventually.最终 所有人都会出现慢慢遗忘的现象 A second type of forgetting- targeted forgetting –第二种是有针对性的遗忘 happens at night while we sleep.发生在我们晚上睡觉的时候 This is when we clear out random, useless tidbits of information we’ve learned during the day这时我们清除白天学到的随机且无用的花边信息 and erase outdated memories.并抹去过时的记忆 For example, if yesterday, you thought the Earth was, say,比如 昨天你认为地球是 a flat disk supported by three elephants,由三头大象支撑的扁平圆盘 and today you learned that the Earth is round,今天你又学到地球是球形的 your brain needs to purge one of these contradictory ideas你的大脑就需要清除这两个互相矛盾的理论之一 hopefully the one about the elephants.希望清除的是大象的那个 In certain stages of sleep,在睡眠的某些阶段 we trim and prune connections between cells我们修剪细胞之间的连接 and erase unneeded memory circuits.并清除不需要的记忆回路 The third type of forgetting is motivated forgetting,第三种是主动遗忘 something we all wish we could do我们总希望自己能够 for one thing or another.主动遗忘这件或那件事 This is when a person intentionally suppresses unpleasant memories.这时人们在有意抑制不愉快的记忆 Forgetting on purpose is a way to regulate our emotions故意遗忘是我们调节情绪的一种方式 and to focus on what needs to be done in the present,让我们专注于当下需要做的事 instead of getting lost in negative memories of the past.而不是迷失在过去的负面记忆中 We may need motivated forgetting to maintain our self-image,我们可能需要主动遗忘来维持自我形象 to maintain confidence, to stay optimistic about the future,保持自信 乐对未来 or to be able to maintain relationships with people who have hurt us.或维持与那些曾经伤害过我们的人的关系 We don’t know exactly how motivated forgetting happens,我们不能确切知道主动遗忘是如何发生的 but part of our brain seems to step in似乎是我们大脑中的一部分介入 and block the troubling memory from being retrieved.阻断了追忆令人不安的记忆 So that even though it’s still somewhere in our brain,所以 虽然它仍在我们大脑中的某处 eventually we can’t find it.我们却找不到它 Our brains have so many ways to forget我们的大脑有很多种方式去遗忘 because forgetting is one of the most important things we do.因为遗忘是我们所做的最重要的事情之一 Forgetting allows us to move past traumatic life events.遗忘让我们能够摆脱过去生活中的创伤 In fact, PTSD may be a problem事实上 人们患上创伤后应激障碍 where someone simply remembers too much.可能只是因为记住了太多东西 Forgetting also allows us to clear out junk.遗忘也让我们能清除垃圾 Imagine every sight, sound, smell, and piece of information想想大脑每天要处理的 your brain processes every day!每个场景 声音 气味和信息 If our brains didn’t sweep out the garbage every night,如果每天晚上不清理这些垃圾的话 we would soon overflow our neural networks with random useless trivia,混乱无用的琐碎信息很快就会挤满我们的神经网络 just like Sherlock Holmes predicted.就像夏洛克·福尔摩斯预测的那样 We also wouldn’t be able to replace things我们也无法用更优质的信息 that are no longer true with better information,剔掉已经失真的信息 update our mental models of the world.更新我们对世界的认识 Deep in the scientific literature在科学文摘中 we find stories of a handful of people who never forget anything.我们发现有少部分人永远不会遗忘任何事 They are so rare that their unforgetfulness has a medical name: hyperthymesia.这非常罕见 医学上称之为:超忆症 The most famous case is Jill Price,最著名的案例是 an American woman now in her fifties.现年50多岁的美国女性吉尔·普莱斯 Starting from age 14,从十四岁开始 Jill’s memory of her life is nearly perfect.吉尔对自己生活的记忆近乎完美 For any date in the past,对于过去的每一天 she remembers what she wore and had for lunch that day,她都记得自己穿了什么 中午吃了什么 key historical events that she paid attention to,她关注的重要历史事件 and detailed incidents from her life.以及生活中的细节 She describes memories playing in her mind in vivid detail她能以生动的细节描述脑海中的记忆 like a video reel that has been enhanced with smells and emotions,像一盘有气味和情感 升华了的录影带 whether the events occurred yesterday or decades ago.无论事情发生在昨天还是几十年前 This might sound like a blessing, especially if you’re in school,这听起来像是幸事 尤其是在上学期间 but Jill has described being haunted by upsetting memories and by regrets,但吉尔称自己会被令人沮丧的回忆和遗憾困扰 because unlike the rest of us,因为不像我们其他人 she can clearly remember every choice she made and how it turned out.她能清楚地记得自己所做的每一个选择以及结果如何 There’s probably something you truly ‘want’ to forget,也许有些东西是你真的想忘记的 like that extremely embarrassing moment in high school比如总在最糟糕时浮现在脑海中的 that always seems to pop up at the worst times.高中时期特别尴尬的瞬间 Can we erase those unwanted memories somehow?我们能以某种方式抹去那些不想要的记忆吗? In an episode of House, MD,在《豪斯医生》的某一集中 Dr. House treated a patient suffering from painful memories豪斯医生通过电休克疗法 by performing something called electroconvulsive therapy:治疗了一个受困于痛苦回忆的病人: controlled electric shocks to the brain.用一定量的电流刺激大脑 People who undergo ECT do lose some memories –接受电休克治疗的人确实会丢失一些记忆 only not necessarily the ones they hope.只是不一定是他们所希望的记忆 When it comes to erasing memories in humans,当谈到消除人类记忆时 our best tool still works like a hammer, not a scalpel.我们最好的工具仍然像把锤子而非手术刀 It’s no accident that our ability to forget,我们的遗忘能力像记忆能力一样 like our ability to remember,是一种复杂且精调过的机制 is a complex and finely-tuned mechanism.这并非偶然 If humans couldn’t remember and learn from important events,如果不能记住重大事件并从中学习 our species probably wouldn’t have survived.人类可能都活不下来 But it seems that being able to forget is just as critical,但似乎遗忘的能力也同样重要 an elementary part of solving this great mystery we call life.是解答我们称之为生命的重大谜题的基础 Stay curious!请保持好奇心! So you probably can’t teach yourself to have perfect memory,你可能无法让自己拥有完美的记忆力 and never forget anything.不忘记任何事 Not without a massive brain injury or something.除非你有严重的脑损伤之类的 But is memorization really the best way to learn something?但是记忆真的是学习的最好方法吗? Memorizing can definitely help you get started with a new concept.记忆绝对可以帮你开启一个新的概念 However, truly understanding it requires much more –然而 真正理解它需要的更多 seeing how concepts are related to each other,了解概念之间的关联 looking for different interpretations, dealing with new information.寻找不同的解释 处理新的信息 These are the skills that will help you learn anything,这些是可以帮助你学习一切的技能 and if you’d like to sharpen your brain and develop these tools,如果你想让大脑敏锐 发展这些技能 then Brilliant could be the place to go for that.那么 Brilliant网站可以帮到你 Check out this Brilliant course on logic and deduction. [screen recording]看看Brilliant上这门逻辑推理课程 [屏幕录制] It’s got fun and challenging riddles and mind-benders broken up into bite size pieces,上面有一条条有趣又具有挑战性的迷题和脑筋急转弯 and they’ll guide you through the problems until you’re a Sherlock Holmes-level logical thinker…引导你解决问题 直到你成为像福尔摩斯一样厉害的逻辑思考者 To support It’s Okay To Be Smart and learn more about Brilliant,支持“聪明刷” 了解更多关于Brilliant的信息 go to brilliant dot org slash BESMART and sign up for free.请登录Brilliant.org/BESMART网站免费注册 Also, the first 200 people that go to that link will get 20% off the annual Premium subscription.前200名点击链接的用户可以享受年费八折的优惠 Oh, pop quiz.来个小测试 What’s the term for when the memory fades over time?记忆随时间衰退的术语是什么? Told you’ll forget.我就说你会忘记吧
  • 2021-10-26911如何改变了摩天大楼的设计September 11, 2001, changed our lives lot.2001年9月11日 我们的生活发生了翻天覆地的变化 Political differences seemed to disappear, at least briefly.政治分歧似乎消失了 至少是短暂的 New security measures filled the world’s airports.新的安全措施遍布了全世界的机场 Thousands of families mourned the loss of loved ones.成千上万的家庭痛失所爱 And, of course, the New York City skyline lacked its two tallest buildings.当然 纽约的天际也失去了最高的两座建筑 But there’s one change that you probably didn’t notice但有个改变你大概没有注意到 because it took place inside new high-rise buildings.因为它发生在新建大楼的内部 And it’s probably not what you’d expect.而这可能不是你期待的 Before we dive in, we want to acknowledge在深入研究之前 我们想说 that this is perhaps the most analyzed event in modern American history.这可能是美国现代史上被分析最多的事件 It was a tragedy.这是一个悲剧 But it occurred nearly 20 years ago,但这件事发生在近二十年前 meaning a significant portion of the American population doesn’t have clear memories,这意味着多数美国人对此已没有清晰的印象了 if any,of what happened.如果有 发生了什么 In order to understand what changed为了弄清发生了什么变化 we first need to outline how the towers were originally designed.首先要概述双子塔当初是如何设计的 The plans for a World Trade Center date back to 1946,世贸中心的建造计划可追溯到1946年 but those were for a single 70-story building但其他那些拥有70年历史的单个建筑 pretty different from the Twin Towers.与双子塔大不相同 The twins were designed by Japanese-American architect Minoru Yamasaki双子塔是由美籍日裔建筑师山崎实设计的 after his firm won the commission in 1962他的公司于1962年获得双子塔的设计委任后 a renowned job that landed him the cover of TIME Magazine.他因这一知名工作登上时代杂志的封面 On April 4, 1973,1973年4月4日 the completed towers debuted as the tallest in the world.竣工的双子塔作为当时世界上最高的建筑首次亮相 But their height wasn’t their only remarkable feature.但高度并非它们唯一的标志性特点 The structural design of the towers, and for that matter,就双子塔的结构设计而言 the architectural design was quite unique.它是相当独特的 This is Ronald Hamburger.这是Ronald Hamburger He was one of a few structural engineers recruited to do a postmortem on the Twin Towers after they collapsed.他是双子塔倒塌后 被聘去事后析误的结构工程师之一 He explained that earlier skyscrapers were built with a mixture of masonry and steel frames他解释道 早期的摩天大楼是砖石和钢架结构 with vertical columns spread throughout the building.整个建筑布满立柱 Picture the Empire State Building想象一下帝国大厦 practically a fortress, with 210 vertical columns throughout the building,它实际上是一座有着210根立柱的堡垒 and fortunately no column-free spaces幸而没有无柱空间 The Twin Towers, on the other hand, were basically “steel tubes.”双子塔就不同了 它们基本上就是“钢管” Steel columns lined the exterior perimeter,钢柱沿排列在外围 connecting to the core of the building via the floors.通过楼层连接到建筑的核心 The floors themselves were made of concrete poured on a steel frame地板本身是由浇筑在钢框架上的混凝土制成 note that this concrete wasn’t providing vertical stability.注意这种混凝土并不能提供垂直稳定性 Just flooring.只是当作地板 That was the work of the core’s 47 steel columns braced with sheetrock.起支撑作用的是内部用石膏板加固的47根钢筋 Finally, also in the core were最后 内部还有 all of the buildings’ elevators, stairwells, and utility shafts.整栋楼里所有的电梯 楼梯井 公用井 And the reason they did that was这么做的原因 so that you could have this massive space of open floor space是使人能拥有较大的地面开放空间 where you can put some desks and workstations可以放一些办公桌和智能终端 that would not be interrupted by columns,而不被柱子阻隔 Each building was about 95% air每栋建筑约95%的部分是空气 so light that they swayed in a strong wind.太轻了 以至于它们会在强风中摇摆 Now, a super-tall lightweight building may sound risky in retrospect.现在想想 一座超高的轻型建筑可能听上去很危险 But the towers were actually quite strong.但双子塔其实非常坚固 The design was highly redundant.它的设计十分冗余 Structural engineers talk about redundancy结构工程师说起冗余 much like a person wearing both a belt and suspenders.就像一个人既系腰带又系背带一样 Either one of them can hold up your pants,两者中任何一个都可以系牢你的裤子 but if one of them fails, you have the other present that can do the job.但如果一个坏了另一个还可以撑住 And this building was highly redundant.况且这座建筑是极其冗余的 Additionally, both buildings were designed此外 这两座建筑的设计 with the prospect of an airplane impact in mind.都考虑到了飞机撞击的可能 See, in 1945, a B-52 accidentally crashed into the Empire State Building on a foggy day.1945年 一架 B-52 飞机在大雾天意外撞上帝国大厦 15 years later, two planes crashed into each other above the city,15年后 两架飞机在城市上空相撞 raining debris over Staten Island and Brooklyn.残骸碎片从史坦顿岛和布鲁克林上空如雨般落下 So designers were aware that aircraft crashing into buildings could happen.因此 设计师意识到会有飞机撞击建筑的情况发生 The World Trade Center towers were designed for the state of the art aircraft of its day,世贸中心双子塔的设计考虑到了当时最先进的飞机 which was a Boeing 707.波音707 But designing a building to resist a 1960s-era plane getting lost in the fog但设计能抵挡1960年代在雾中迷失的飞机的建筑 isn’t the same as designing one to resist a larger plane与抵挡以最高速度飞行 being steered at top speed to intentionally cause damage.故意造成损坏的更大飞机不同 Near major airports jetliners are limited in speed to 180 miles an hour.在主要机场附近 喷气式客机的速度限制为180英里/小时 The aircraft that went into the Twin Towers were traveling in excess of 400 miles per hour.撞击双子塔的飞机飞行时速超过400英里 I don’t think anyone thought that was a credible event prior to the World Trade’s我想在世贸事件发生前 没人会相信这是真的 For our viewers who are just tuning in right now,刚刚调到频道的观众们 a twin-engine plane or possibly a 737 passenger一架双引擎飞机 或者可能是一架737客机 jet flying into the World Trade Center撞向世贸中心 It appears to be still embedded inside the building.它似乎还嵌在大楼里 The impact damaged both the outer shell and the core.撞击破坏了大楼的外壳和内部 But both towers kept standing because of redundancy但因其冗余结构 双子塔仍伫立着 their weight was able to shift away to unaffected columns.它们的重量转移到了未受影响的柱子 But here’s the problem:问题来了: the impact had scraped the fire-resistant coating off the steel columns and beams,撞击使钢筋柱和房梁的防火层解体 and the jet fuel had ignited a raging fire.航空燃油引起了熊熊烈火 This heated the steel to an unsustainable temperature.烈火将钢加热到无法承受的温度 The jet fuel burned itself off in a few minutes.航空燃油虽在几分钟内燃烧殆尽 But what it did is it ignited all the contents of the building但却点燃了建筑里面的东西 The heat of the fires could not and did not melt the steel.火的热量无法也没有熔化钢筋 But it’s not actually necessary to melt steel to make the buildings come down…但要使建筑倒塌 也不必熔掉钢筋 When you reheat steel to about 500 degrees Fahrenheit,当钢被反复加热到大约500华氏度时 it starts to lose some of its strength and stiffness.它开始丧失部分强度和刚度 Eventually, the floors above the impacted areas became too heavy最终 被撞区域上方的地板对弱化的钢材而言太重 for the weakened steel to support,使其无法支撑 and both buildings collapsed.两座建筑物都倒塌了 You might think this tragedy would have compelled us你可能会想 这桩悲剧会促使我们 to make drastic changes to the rules of how we build skyscrapers.对建造摩天大楼的习惯做出重大改变 And we have in some ways that we’ll get to in a minute.我们一会儿会讲到在某些方面的确如此 But structurally…但就结构上来说 Building code requirements have not changed a lot.建筑规范要求没有太大变化 The people who had a vote, felt拥有投票权的群众认为 that the added cost of the measures提议增加费用的方案 that were proposed did not make sense,是毫无意义的 given what was perceived to be…the extreme rarity of such an attack.他们觉得 这样的攻击极其罕见 The years since 2000 have seen a rise in supertall buildings around the world2000年以来 全世界的超高建筑不断增加 nearly 9,000 skyscrapers were added from 2000-2020.2000至2020年间 就添了近9000座摩天大楼 And even though resisting aircraft impact isn’t a requirement,即使没必要预防飞机的撞击 many of them are much stronger anyway由于不同的设计和材料 because of different designs and materials.它们中的许多都要坚固得多 Rather than using only steel construction.比起使用钢结构 Now most high-rise buildings, supertall buildings, are constructed all using concrete walls in the form现在大多数高层建筑 超高层建筑 都是用混凝土墙建造的 And then steel framing around the perimeter然后是周围的钢架 and then the floor system between the floor and the exterior wall.再是地板和外墙之间的地板系统 Take the new World Trade Center, for instance.以新世贸中心为例 It’s basically a hefty three-foot thick concrete core它基本上是一个三英尺厚的混凝土核心 with a glass skin.外加一层玻璃 The end result is a stronger building.最终的结果是一座更坚固的建筑 This is because concrete is far more fire-resistant than steel,这是因为 混凝土比钢材更耐火 but it’s also because concrete itself has become much stronger.而且混凝土本身也更结实了 So concrete, typical concrete, conventional concrete we use all the time has a strength of 4,000 psi所以混凝土 典型的混凝土 传统的混凝土 我们一直使用的混凝土强度为4000psi Quick pause – psi stands for “pounds per square inch.”暂停一下 psi代表“磅每平方英寸” It refers to the total weight the concrete can support before failing.它是指混凝土在垮掉前所能承受的总重量 The concrete used in the floors of the Twin Towers双子塔地板所用的混凝土能承受的 ranged from 3,000-4,000 psi.最大压力在3000-4000psi之间 But that pales in comparison to the strength of newer concrete we use today.但这与如今使用的新型混凝土的强度相比就相形见绌了 The core of the new 1 World Trade Center, for example, uses concrete ranging in strength像新世贸中心1号楼的核心使用的混凝土的强度 from 8,000 to 14,000 psi.在8000至14000psi之间 And that’s not even the strongest concrete that exists!而这甚至也不是目前存在的最坚固的混凝土 This is a relatively new type of concrete这是一种相对较新的混凝土类型 called ultra high performance concrete.叫做超高性能混凝土 The high-strength concrete is roughly高强度混凝土能承受的最大压力 from 15,000 psi to 30,000 psi大约在15000至30000psi之间 So greater safety protocols and stronger materials因此 更严格的安全规程和更坚固的材料 have together created a wave of robust new skyscrapers共同创造了一波坚固的新摩天大楼 even if protecting against future airplane hijackings isn’t explicitly required即使防范未来的飞机劫持并不是明确的要求 But Hamburger told us that some of the world’s newest high-rise buildings have been constructed但Hamburger告诉我们一些世界最新的高层建筑都采取了 with measures to protect against terrorist attacks.防范恐怖袭击的措施 No one will tell you which buildings have been constructed with it.没人会告诉你哪些建筑釆取了这样的措施 No one will tell you what weapon they’ve been designed to defend against,没人会告诉你他们设计了什么武器来防御 but some of them have been voluntarily designed to be better able to resist such events.但其中一些是自愿设计的 以便更好地抵御此类事件 Karin: do…do you know which ones?Karin:你知道是哪些吗? I know some of them. I don’t know all of them, and I won’t talk[laughter]我知道其中一些 但我并不知道全部 而且我也不会说的[笑声] Post-9/11 code changes actually revolved less around structural choices911事件后的法规变化实际上并不围绕结构抉择 and more around “means of egress.”更多的是围绕“出口方式” In layman’s terms: exits.用外行人的话来说就是出口 The designer of the World Trade Center其实世贸中心的设计者 actually used a system that are called scissor stairs用了一种称作剪刀楼梯的系统 But stairs were actually very close to each other within the core.但其实核心里的楼梯彼此紧挨着 So when the plane went into the building, they managed to block both sets of stairs所以当飞机撞向建筑时 他们设法阻塞几组楼梯 meaning that, even though people trapped inside也就是说 即使困在里面的人理论上 theoretically had time to escape, they couldn’t.有时间逃脱 实际上却不能 So one of the most significant things we’ve done is we’ve changed the building code因此我们做的最重要的事情之一就是改变了关于 to require more separation between the places where stairways are located,要求楼梯的位置之间有更多间隔的建筑法 so that it is more probable that…因此 更可能…… there will be at least one stairway available.至少会有一个楼梯可用 Additional code changes included widening stairways另外的法律修改包括扩大楼道 self-luminous exit pathways;出口途径自发光 third stairways in buildings over 420 feet建筑内的第三楼道超过420英尺 boosting overall fire resistance; and more.提高整体防火能力等等 These changes reflect less of a focus on saving the buildings,这些改变反映人们对保护建筑的关注减少 and more on making sure the people inside而更关注的是确保里面的人 have time to get out in an emergency.有时间在紧急情况下离开
  • 2021-10-26为什么阿什哈巴德是世界上生活成本最高的城市Here’s a crazy trick question: what’s the most exp… oh you already got it?有个疯狂的难题:什么是最贵……哦 你已经知道了 Because it was in the title of this video?因为视频的标题已经写了 Right, ok, so… then let’s just jump right in.好吧 那……直接开始吧 Now, you might remember Ashgabat from that time you Googled如果你在谷歌上搜索过 “土库曼斯坦的首都在哪” “What is the capital of Turkmenistan”“天哪 我烦透了 请让我摆脱贫穷吧” “oh god I am so bored please put me out of my misery”那你可能还记得阿什哈巴德 Otherwise, there’s a good chance you haven’t heard of it.否则 很有可能你从没听说过它 So, how did it rise through the ranks of the most expensive cities in the entire world?那么它是如何跻身全球最贵城市之列的? Well, a lot of that has to do with the way that cost of living is calculated in the first place.首先 它与生活成本的计算方式有很大关系 You see, generally, a cost-of-living index pools together the local cost of一般来说 生活成本指数将人们 a number of different items that one might regularly spend money on可能经常消费的一些不同项目的当地成本汇总到一起 things like rent, utilities, food, clothing, transportation, half as Interesting merch, etc.比如租金 水电 食物 服装 交通 不怎么有趣的商品等 Since these prices are subject to different levels of fluctuation由于这些价格会有不同程度的波动 cost-of-living indexes also take into account the stability of the local economy生活成本指数也顾及了当地经济的稳定性 things like inflation, exchange rates, and overall consumer confidence.比如通货膨胀 汇率 整体消费者信心等 “But Sam!” you might be saying“但是山姆” 你可能会这样说 rudely interrupting my whole explanation of cost-of-living indexes粗鲁地打断我对生活成本的整个解释 “Don’t people have different needs in different countries?”“难道不同国家的人没有不同的需求吗?” “Like, what about my friend from Canada who doesn’t need to worry about syrup prices”“比如 我的加拿大朋友不需要担心糖浆的价格” “because his government socialized syrup 150 years ago”“因为他的政府在150年前就把糖浆社会化了” “allowing him to take syrup from any grocery store for free”“允许他从任何杂货店免费带走糖浆” Well, while that’s definitely not true and the term for that is “shoplifting,”好吧 虽然这绝对不是真的 而且这种行为叫“入店行窃” still, it’s a decent point不过 这还是一个不错的观点 cost of living can be difficult to standardize across different countries生活成本在不同国家很难标准化 because people have different standards of living因为人们的生活水平不同 and are supported by their governments to different extents.而且受到政府不同程度的补贴 So, many of the most popular indexes solve this所以许多广泛应用的指数会通过观察 by looking at cost-of-living for a hypothetical expatriate moving to a new city一个假想的移居到新城市的外籍人士的生活成本 以解决此问题 this means standards of living similar to developed countries这意味着生活水平与发达国家相似 and not taking into account government-subsidized amenities而且不用考虑政府补贴的便利设施 that last point is particularly important when it comes to talking about Turkmenistan当谈到土库曼斯坦 最后一点尤其重要 but I’ll explain what I mean in a minute.但我会在一分钟内做出解释 For now, all you need to know is:现在 你所需要知道的就是 expensive jeans + unstable economy = you get to be on this Wikipedia page.昂贵的牛仔裤+不稳定的经济=你会登上这个维基百科网页 Got it? Good.懂了吗? 很好 Now let’s talk about how Ashgabat does that better than anyone else.现在我们来谈谈阿什哈巴德在这方面做的怎么比别的城市好 While Turkmenistan might be home to the most expensive city in the world虽然土库曼斯坦可能是世界上生活成本最高的城市 that doesn’t mean that things are all champagne and…那也并不意味着一切都是香槟 whatever kind of cereal rich people pour their champagne on.或是富人们把香槟倒在哪种麦片上 In fact, it’s kind of the opposite: Turkmenistan is currently facing事实上 情况恰恰相反 to put things lightly往轻了说 a devastating economic crisis土库曼斯坦目前正面临一个毁灭性的经济危机 coupled with a slew of escalating humanitarian disasters.和一系列不断升级的人道主义灾难 I guess that’s not putting it very lightly我想我也没有说的很轻 but there aren’t too many ways to put it.但也没有太多方式来描述它 You see, when Turkmenistan gained independence in 1991你看 当1991年土库曼斯坦获得独立时 it was well-positioned to become one of the world’s leading ‘stans’它还处于有利地位 能够成为世界领先的“斯坦国”之一 it was sitting on the 4th largest natural gas reserve in the world它拥有世界第四大天然气储量 representing about 10% of Earth’s known supply约占地球已知供应的10% and a decent amount of oil还有相当多的石油 and throughout the early 2000s gas prices were higher在整个20世纪初 天然气价格都很高 than the Exxon executives celebrating how high gas prices had gotten.比埃克森石油公司的高管庆祝天然气价格上涨时还高 The problem, though, is that for the first 15 years of Turkmenistan’s independence,然而 问题是 在土库曼斯坦独立的前十五年 all of that gas money was being managed by this guy: Saparmurat Niyazov.所有的天然气价格都是由萨帕尔穆拉特·尼亚佐夫控制的 Niyazov was, to put things lightly, one of the most self-absorbed说轻点 尼亚佐夫是中亚地区最自私 unhinged, and despotic dictators to ever rule in Central Asia.最精神错乱 最专横的独裁者之一 Man, I’m really not good at putting things lightly.朋友 我真的不擅长轻描淡写 But basically, Niyazov wanted to rebuild Turkmenistan in his own image:但基本上 尼亚佐夫想以自己的形象重建土库曼斯坦 he renamed January after himself and April after his mother,他以自己的名字命名一月 以母亲的名字命名四月 he banned dogs because he didn’t like the smell,他禁止养狗 因为不喜欢狗的气味 he banned smoking after he had to quit smoking himself,他禁止吸烟 在他不得不戒烟之后 and he even put his cat in charge of their airforce.他甚至让他的猫掌管空军 That last fact was a joke, but the point is that you’d have believed it.最后一点是个玩笑 但重点是你会相信 Perhaps his most substantial project, though, was Ashgabat或许他最有价值的“功绩”就是阿什哈巴德 while most of the country wallowed in widespread poverty当全国大部分地区普遍深陷贫困的时候 Niyazov spent huge chunks of Turkmenistan’s revenue on renovating the country’s capital,尼亚佐夫用土库曼斯坦的大量收入翻修首都 bulldozing residential neighborhoods and铲平居民区 replacing them with luxury marble high-rises that no one could afford to live in.用没人住得起的豪华大理石高楼取而代之 This has left the center of the city virtually empty,这使得市中心几乎空无一人 serving more as a statement of national wealth更多的是作为国家财富的象征 than as a practical place to live.而不是实用的居住地 But much like a puzzle that’s only had one piece placed但这很像拼图只补了一块 that’s only one piece of the puzzle就只是拼图的一块 In 2014, gas prices began to plunge在2014年 天然气价格开始暴跌 and major international brands like Levi’s, Nike, and Amazon李维斯 耐克 亚马逊等主要国际品牌 fell prey to the SJW mob成为社会正义人士的牺牲品 and decided to stop purchasing Turkmenistan’s slave-harvested cotton.决定不再购买土库曼斯坦奴隶采摘的棉花 With such a hard hit to their economy,由于经济受到如此严重的冲击 Turkmenistan drastically reduced imports, primarily food products土库曼斯坦大幅减少了进口 主要是食品进口 and the local price of those items naturally started to skyrocket.随后这些商品的当地价格自然开始飙升 To further complicate matters, Turkmenistan’s currency, the Manat更复杂的是 土库曼斯坦的货币马纳特 began rapidly declining in value during the economic crisis在经济危机期间开始迅速贬值 so the government bravely declared that “no it isn’t”所以政府极力否认这个事实 and locked the official exchange rate at 3.50 Manat to the dollar.并将官方汇率锁定在1美元兑3.5马纳特 While this might seem like it would fix the problem如果你是一个四岁的孩子 if you’re a four-year-old or a very corrupt five-year-old或是一个非常堕落的五岁孩子 这可能会解决问题 it turns out it just makes the problem worse.但事实证明 这只会让事情更糟 As the practical purchasing power of the Manat began to decline even further随着马纳特的实际购买力开始进一步下降 and the price of products in Manat went up to compensate the locked exchange rate以马纳特购买的产品价格上涨 来补偿被锁定的汇率 meant that the inflated price of those products also inflated their official value.这意味着这些产品的价格上涨也抬高了它们的官方价值 In Ashgabat, a gallon of milk might cost you about 50 Manat在阿什哈巴德 1加仑牛奶可能会花掉你50个马纳特 with a practical, black market exchange rate of 40 Manat to the dollar, this isn’t too outrageous.在实际的黑市上 1美元兑40马纳特的汇率并不离谱 But with the official exchange rate of 3.50 Manat to the dollar但官方汇率是1美元兑3.5马纳特 and this is what the cost-of-living indexes are forced to use这就是生活成本指数被强制使用的汇率标准 —this means a gallon of milk technically costs about 15 dollars.这意味着1加仑牛奶理论上要花费15美元 The same goes for a month of internet service at 186 dollars,同样 一个月的网费要花186美元 or a pair of blue jeans at 112 dollars.一条蓝色牛仔裤要花112美元 If you plug those numbers into our equation from earlier,如果你把这些数字代入到我们之前的等式 I’d say that the math checks out.我会说数字做了很好的证明 But wait, if Ashgabat is so expensive and Turkmenistan is so poor但等等 如果阿什哈巴德这么昂贵 土库曼斯坦又这么穷 how can anyone afford to live there?人们怎么能住得起呢 Well, the simple answer is… they can’t.好吧 答案很简单 他们住不起 Since 2003, Turkmenistan has had to foot the bill从2003年开始 土库曼斯坦就必须负担公民的 for its citizens’ electricity, gas, and water,电费 天然气费 水费 and set up government-subsidized stores并建立了政府补贴的商店 for people to buy food that’s well-under market price…以便人们去买低于市场价格的食物 that is, until 2019, when they stopped paying for utilities事实却是 到2019年 他们停止支付公共花销 and sent police to break up long lines of starving people outside their state stores.并派警察去驱散在国家商店外排长队的人 So, if you want to experience the thrill of spending 15 dollars on milk,所以 如果你想体验花15美元买牛奶的刺激 you’re probably better off just going to Whole Foods.可能最好还是去全食超市 If, rather, you get a thrill out of spending $15 on something worth more than $15,更确切的说 如果你因花15美元买了价值超过15美元的东西而兴奋 then boy do I have something for you.那我推荐个东西给你 So, Nebula, right?是星云网站 不错吧 It’s the streaming platform founded by myself and my creator friends,这是一个流媒体平台 由我和我的朋友共同创建 designed from the ground up to be the best home for our content它完全是为我们的内容设计的 meaning no ads getting in the way这意味着没有广告的阻碍 or algorithms telling us what kind of videos we can make.也没有算法要求我们必须制作哪种视频 Plus, the financial model means we can make big-budget Nebula Originals–另外 财务模式意味着我们可以制作大预算的《星云始祖》 in fact, we filmed one for HAI last month,事实上 我们上个月为平台拍摄了一个作品 and it’s in post-production right now.现在正在后期制作中 Of course, what makes this the best use of $15 ever is the Curiosity Stream/Nebula bundle deal.当然 让15美元发挥最大价值的是与网站捆绑交易 You head to CuriosityStream.com/hai, sign up for any subscription–你可以登录CuriousityStream.com/hai 订阅任何栏目 including the annual one on sale for about $15 a year包括每年大约15美元的年度订阅 and you get free access to Nebula.你就可以免费访问星云平台 That means you can watch anything from all your favorite Nebula creators, support these creators,这意味着你可以观看平台上所有你喜欢的视频 支持创作者 and watch anything from CuriosityStream’s massive catalogue of none fiction shows in documentaries并观看平台上大量的非小说类纪录片 including Hot Roads––about the world’s most dangerous roads包括Hot Roads 是关于世界上最危险的道路 and those that use them.以及使用这些道路的人 All in all, this is well worth the $15 a year it’ll cost you总之 这很值得你每年花15美元 so click the button on screen所以点击屏幕上的按钮 or head to CuriosityStream.com/ hai to sign up today.或者今天就去CuriosityStream.com/hai上注册吧
  • 2021-10-26我们如何知道爱因斯坦的广义相对论不完全正确Today I want to explain今天我想和大家说说 how we know that the way Einstein thought about gravity cannot be correct.我们是如何知道 爱因斯坦对引力的看法是不正确的 Einstein’s idea was that gravity is not a force,爱因斯坦的观点是 引力不是力 but it is really an effect caused by the curvature of space and time.实际上它是时空弯曲造成的效应 Matter curves space-time in its vicinity,物体使它周围的时空发生弯曲 and this curvature in return affects how matter moves.这种时空弯曲又反过来影响物体的运动 This means that, according to Einstein,这意味着 根据爱因斯坦的理论 space and time are responsive.时间和空间是可变的 They deform in the presence of matter时空会因物体的存在而扭曲 and not only matter, but all types of energies,并且不光是物体 任何形式的能量 including pressure and momentum flux and so on.如压力 动量通量等 都会让时空扭曲 Einstein called his theory “General Relativity”爱因斯坦称这个理论为“广义相对论” because it’s a generalization of special relativity.因为它是狭义相对论的广泛化 Both are based on “observer independence”,两者都是建立在“独立于观察者”的基础上 that is the idea that the laws of nature should not depend on the motion of an observer.其理念是自然法则不应受观察者运动状态的影响 The difference between General Relativity and Special Relativity is广义相对论和狭义相对论的区别是 that in Special Relativity space-time is flat, like a sheet of paper,在狭义相对论里 时空是扁平的 就像一张纸 while in General Relativity it can be curved, like the often named rubber sheet.而在广义相对论里 时空是像橡胶板那样可弯曲的 General Relativity is an extremely well-confirmed theory.广义相对论得到了广泛的证实 It predicts, for example, 例如 它预测 that light rays bend around massive objects, like the sun,光在经过像太阳之类的大质量物体时会弯曲 which we have observed.我们已经观察到这一点了 The same effect also gives rise to gravitational lensing, which we have also observed.这个效应还会导致引力透镜 我们也观察到了 General Relativity further predicts that the universe should expand, which it does.广义相对论进一步预测宇宙会膨胀 确实如此 It predicts that time runs more slowly in gravitational potentials, which is correct.它还预测引力会使时间变慢 同样没错 General Relativity predicts black holes,广义相对论预测了黑洞的存在 and it predicts just how the black hole shadow looks like, 还预测了黑洞阴影是什么样的 which is what we have observed.我们看到的正是如此 It also predicts gravitational waves, which we have observed.它还预测了引力波 这也被我们观察到了 And the list goes on.我还能接着举例 So, there is no doubt that General Relativity works extremely well.所以毫无疑问 广义相对论非常有道理 But we already know that it cannot ultimately be the correct theory for space and time.但是 我们知道它不可能是关于时空的终极理论 It is an approximation that works in many circumstances, but fails in others.它接近正确理论 能解释很多现象 但不是万能的 We know this because我们知道这一点是因为 General Relativity does not fit together with another extremely well confirmed theory,它与另一个被广泛证实的理论无法统一 that is quantum mechanics.那就是量子力学 It’s one of these problems that’s easy to explain but extremely difficult to solve.这个无法兼容的问题 解释起来容易但解决起来却很难 Here is what goes wrong if you want to combine gravity and quantum mechanics.如果要结合引力理论和量子力学 问题就来了 We know experimentally that particles have some strange quantum properties.通过实验 我们知道粒子有某些奇特的量子特性 They obey the uncertainty principle这些粒子遵循不确定原理 and they can do things like being in two places at the same time.比如 粒子够能同时处于两个不同的位置 Concretely, think about an electron going through a double slit.举个实例 想一下电子穿过双缝的实验 Quantum mechanics tells us that the particle goes through both slits at the same time.量子力学告诉我们 粒子会同时穿越两条缝隙 Now, electrons have a mass电子具有质量 and masses generate a gravitational pull by bending space-time.而大质量物体 通过弯曲时空产生引力 This brings up the question,这就带来一个问题 to which place does the gravitational pull go如果一个电子同时穿越两个缝隙 if the electron travels through both slits at the same time.那么引力会去哪里呢? You would expect the gravitational pull to also go to two places at the same time.你可能会想 引力也同时出现在了两个地方 But this cannot be the case in general relativity,但根据广义相对论 这是不可能的 because general relativity is not a quantum theory.因为广义相对论不是量子理论 To solve this problem, we have to understand the quantum properties of gravity.要解决这个问题 我们必须搞清楚引力的量子特性 We need what physicists call a theory of quantum gravity.需要物理学家称之为“量子引力学”的理论 And since Einstein taught us that gravity is really about the curvature of space and time,既然根据爱因斯坦的学说 引力其实和时空弯曲有关 what we need is a theory for the quantum properties of space and time.那么我们所需的 是关于时空的量子特性的理论 There are two other reasons how we know that General Relativity can’t be quite right.基于另两个理由 也可知广义相对论不完全正确 Besides the double-slit problem, there is the issue with singularities in General Relativity.除了双缝实验 广义相对论还遇到了奇点的问题 Singularities are places奇点指的是 where both the curvature and the energy-density of matter become infinitely large;时空曲率无限大 且能量密度无限大的点 at least that’s what General Relativity predicts.至少广义相对论是这么预测的 This happens for example inside of black holes and at the beginning of the universe.奇点出现在诸如黑洞内部 还有宇宙初期等 In any other theory that we have, singularities are a sign that the theory breaks down在现有任何其他的理论中 奇点都代表着该理论的终点 and has to be replaced by a more fundamental theory.因此 势必要被一种更基本的理论所替代 And we think the same has to be the case in General Relativity,我们认为广义相对论也不例外 where the more fundamental theory to replace it is quantum gravity.取代它的是一种更为基本的量子引力理论 The third reason we think gravity must be quantized is引力必须量子化的第三个理由是 the trouble with information loss in black holes.为解决黑洞信息丢失的难题 If we combine quantum theory with general relativity如果在引力不量子化的情况下 but without quantizing gravity,结合量子理论和广义相对论 then we find that black holes slowly shrink by emitting radiation.那就会发现 黑洞因散发辐射而慢慢变小 This was first derived by Stephen Hawking in the 1970s这个理论最早于20世纪70年代由斯蒂芬·霍金提出 and so this radiation is also called Hawking radiation.因此黑洞辐射又名“霍金辐射” Now, it seems that black holes can entirely vanish by emitting this radiation.黑洞似乎能通过散发辐射而完全消失 Problem is, the radiation itself is entirely random 问题是 辐射本身是完全不可思议 and does not carry any information besides the temperature.不携带除温度外的任何信息 So when a black hole is entirely gone and all you have left is the radiation,那么当黑洞彻底消失时 剩下的只有辐射 you do not know what formed the black hole.就没法知道黑洞是由什么构成的 Such a process is fundamentally irreversible and therefore incompatible with quantum theory.这个过程完全不可逆 因此无法和量子理论相容 It just does not fit together.不仅仅是无法调和 A lot of physicists think that to solve this problem we need a theory of quantum gravity.许多物理学家认为 要解决这个问题得靠量子引力学 So this is how we know that General Relativity has to be replaced by a theory of quantum gravity.由此可知 广义相对论必将被量子引力学所取代 This problem has been known since the 1930s.这个问题在20世纪30年代就提出了 Since then, a lot of attempts has been made to solve it.此后 物理学家们做了很多努力来尝试解决它 I will tell you about this some other time, so don’t forget to subscribe.我会在今后的节目中讲 别忘了订阅哦
  • 2021-10-17垃圾食品是如何干扰你的大脑的[音乐][INTRO ♪] 众所周知 垃圾食品 虽然它不健康 但是 很好吃Junk food: you know it’s not healthy, butit’s so good. 有时候 很难拒绝它And sometimes, it’s just too hard to resist. 科学家曾经试图弄清楚为什么垃圾食品And scientists have been trying to figureout why junk foods 能够如此风靡一时have so much power over us for a while. 根据《细胞代谢》杂志昨天刊登的一篇研究According to a study published yesterdayin the journal Cell Metabolism, 这可能与it probably has a lot to do with the fact that 垃圾食品大都包含脂肪和碳水化合物 有关they’re usually packed with both fat and carbs. Pff, 我的最爱my favorite! 研究者发现当脂肪和碳水化合物这两种营养素混合在一起时The researchers found that the reward centersof our brains 大脑的奖励中心的活跃度are more active when those nutrients are combinedin a snack— 大大超出你的期待above and beyond what you would expect 如果你只添加脂肪和碳水化合物if you just added the fat and the carbs together. 这就是为什么奶昔 薯条Which is why milkshakes, and french fries, 薯条蘸奶昔会如此诱人and dipping your french fries into milkshakes. 这就意味着And that means that it ’ s not 垃圾食品基本上干扰了大脑 现在just you—junk food basically hacks our brains. Now, 有一些现象可以显示there have been hints to this phenomenon forsome time. Mice, 比如for example, 如果只给老鼠吃碳水化合物或脂肪 老鼠就会显瘦can stay trim if they ’ re given either carbs or fat to eat, 但是如果老鼠吃了碳水化合物和脂肪的混合物的话but they pack on the pounds 老鼠整体重量就会增加if they ’ re given a mix of the two. 但很难弄清楚对大脑的影响But it was less clear how that plays out 或者说 对人的影响in the brain, or how it applies to people. 所以德国和美国的神经病学家和生理学家So neurologists and physiologists in Germanyand the US 建立了一种set up a kind 参与者对零食竞标的食物拍卖of food auction where participants bid for snacks 同时 功能磁共振成像检测参与者脑中的活动while the activity in their brains was measuredwith fMRI. 各种零食中的卡路里大多来自碳水化合物The calories in the various snacks were eithermostly from carbs, 脂肪 碳水化合物和脂肪的混合物mostly from fat, or from a mix of both. 食品按大小分类 每一个种类都包含And the items were sized so that each categorycontained 同样数量的卡路里 从能量方面来讲 所有东西都平等对待the same number of calories, to make them equal from an energetic perspective. 实验小组也尽力确保The team also made sure 所有的食物都是在上一次实验中我们所熟知的和喜爱的that all the foods were similarly well known and liked in a previous experiment. 这样 就会不偏不倚That way, the group couldn ’ t prize any set of foods over the others. 但是 参与者们都在套餐提高标价But the participants consistently put higherbids on the combo foods— 比如 巧克力曲奇饼干 方块糖things like chocolate chip cookies and candy bars— 而不是 像 坚果 奶酪 咸饼干这样的食物rather than things like nuts, cheese, or crackers. 目的是为了提供更多This willingness to shell out more 与包含脂肪和碳水化合物的食物相关的for the foods that had both fat and carbs 大脑区域的反射was associated with more of a response inbrain regions 或奖励 终脑皮层的顶部associated with reward, like the top partof the striatum. 研究者怀疑这也许是因为The researchers suspect this may be becausewe have 脂肪和碳水化合物的不同奖励方式separate reward pathways for fats and carbs, 结合物食物同时表现有不同奖励方式both of which are simultaneously turned onby the combo foods. 研究者认为这 就像是 同时奖励电路And they think this, like, simultaneous reward circuit 大脑如火中烧 只是不知道该如何处理而已firing is something our brainsjust don’t know how to handle. 如果以我们的祖先为例 这也确实行得通That actually makes sense if you look at ourancestors. 远古时期 人们每次大都吃一种食物组For eons, people mostly ate one food group 当条件允许的时候at a time, like when it became available— 一天吃肥肉食物 下一天 吃甜蜂蜜 或浆果食物fatty meat one day, sugary honey or berries the next. 他们确实没有太多的其他的选择They didn’t really have the option to do anything else 因为几乎没有食物是包含大量碳水化合物和水because very few foods are naturally richin carbs and fat. 农业使得营养组合混合在食物中变得更加容易Agriculture made it easier to mix nutrientgroups in meals, 但是but it still wasn ’ t 直到150年前 我们开始真正制作until the last 150 years or so that we started actually making 包含具有更多卡路里的所有营养物质的单一食品名目single food items that contain a dozen or more calories of each nutrient type. 所以 对于 绝大部分进化历史So for the vast majority of our evolutionary history, 我们的大脑 不需要努力地评估包含碳水和脂肪食物的营养价值our brains simply haven ’ t had to try to estimate the nutritional value of fatty, carb-filled foods. 研究者也发现 人们并不擅长做这种判断The researchers also discovered that we ’ re pretty terrible at making such judgements. 当他们要求参与者去判断参与者所竞标的在零食中的种类When they asked the participants to guess the calories in the snacks they were bidding on, 当涉及到碳水类食物和组合食物 参与者并不能给出答案they kinda failed when it came to the carb-y and combo foods. 研究者甚至可以把一部分大脑区分为The researchers even identified a part 梭状回of the brain called the fusiform gyrus— 一个基于大脑的重要的长条区a long strip that’s at the base of our brains—that ’ s important 用来做出各种判断 所以for making these kinds of estimations. So, 如果我们不能if we can’t 在涉及到碳水时 评估分类estimate calories very well when carbs are involved, 我们会从脂肪碳水组合物中得到更大的奖励and we’re getting a bigger reward from thosefat/carb combinations, 需要花费更多去解释为什么that goes a long way to explaining why 会如此困难it’s so hard 当我们携带甜甜圈作为食物 而我们不能吃太多甜甜圈for me to not eat more donuts when somebody brings donuts in to work. 我的意思不是你不能携带甜甜圈 把它当食物I ’ m not saying I resent you for bringing the donuts in, 但是 就是要少吃but it’s just hard, okay? 甜甜圈很好吃They’re so good! 即使不好吃 我也要一直吃 最终Even when they’re not that good I keep eating them. Eventually, 科学家可能用这些信息scientists may be able to usethis information 更好地解释吃得过多和肥胖to better understand overeating and obesity. 幸运地是 这意味着And hopefully, that means they 他们能想出can come up with ways for people 让人们做更好食物选择的方法to make better food choices, 即使他们被垃圾食品所环绕even when they’re surrounded by lots of junk, 正如我们经常吃垃圾食品一样as we so often are. 我们下一个主题 更古怪Our next topic, weirdly enough, 是关于众多稀有天然食物的一种is about one of those rare natural foods 这种食物包含丰富的碳水化合物和脂肪that’s rich in the carb and the fat department. 非洲猴面包树能生产一种包括含淀粉的果肉和含大量脂肪的果核的水果African baobab trees produce fruits that have a starchy pulp and a fatty seed. 这样So in a way, that makes them, like, 这就像是一种原始的垃圾食品kind of a proto-junk food, 除此以外 它们还包含纤维和蛋白质except that they’re also packed with fiber and protein, 所以这种水果也十分健康so they ’ re pretty healthy. 问题是The problem is, 《天然植物》杂志这周发表了一篇文章a new report out this week in the journal Nature Plants 文章指出 很多最大的年龄最大的猴面包树found that many of the biggest and oldestbaobabs— 已经养活人们超过一千多年了some of which have been feeding people forthousands of years— 这些树正在莫名其妙地消亡are inexplicably dying out. 国际研究对于调查了全球60棵树The international research team surveyed 60trees across the globe, 检测他们的健康程度 和他们的体积checking on their health, measuring their size, 提取木头样品来评估他们的树龄and taking wood samples to estimate their ages. 你也可能觉得你可以While you might think you could just, like, 像判断其他树的树龄一样 通过计算树的年伦来评估树龄count the rings like other trees, 猴面包树一生可以生长超出树干的年伦baobabs can grow more than one trunk throughouttheir lives. 这样 有时会创造出一种看起来是一个大的树干These sometimes fuse together, creating whatlooks like one big trunk, 但是中部是空白的假象but inside there are open spaces. 这种复杂确实很难去判断他们的树龄And this complexity makes it really hard todate them— 猴面包树的结构很古怪the baobab ’ s structure is so wacky 树龄并不能说明什么 所以that rings don ’ t tell you very much. So, 科学家依靠特殊的放射性碳来记录日期the scientists relied on special typeof radiocarbon dating instead. 这种方法 使用很少部分的样品In this method, you use a very small sample 从大量的树中from multiple parts of the tree, 计算所有种类碳原子的数量and count the number of all the different types of carbon atoms, 你就能得到一个日期评估结果which can then give you a date estimate. 队伍发现很多树The team found that many trees were more 超过了一千年than 1,000 years old, 其中有一棵树几乎有2500 的树龄including one that was nearly 2,500 years old, 这个星球上最古老的开花的树 但是making it the oldest flowering tree on theplanet. But, 在一个可怕未预期的扭曲中 他们也发现in a horrible and unexpected twist, theyalso discovered that 13棵最古老树中有9棵9 of the 13 oldest trees and 5 6棵最大的树中有5棵 已经死了of the 6 biggest trees were dead 活着之前一个树干已经死亡or had at least one trunk that was dead. 死亡发生在上一个12年之内And those deaths all happened within the last12 years. 科学家不能解释这是为什么Scientists aren’t sure why this is happening, 虽然他们觉得天气变化是主要原因although they suspect climate change mightbe to blame. 越来越高的温度 和越来越多的干旱With warmer temperatures and more drought, 树极力争取足够的水分来支撑他们庞大的框架the trees might be struggling to get enough water to support their large frames. 但是 需要进一步研究来确认这一怀疑But further research is needed to confirmthat suspicion. 所以 现在 关键在于So now, the race is 弄清楚到底发生了什么on to figure out exactly what ’ s going on 在我们频道永远消失之前before we lose these iconic trees for good. 谢谢收看科学秀的本期视频Thanks for watching this episode of SciShow! 如果你想继续了解If you want to keep learning 我们生活的这个古怪的世界about this wacky world we live in, 包括实时观看最新信息including staying up to date with all the new, 令人振奋的科学研究exciting scientific research, 请前往油管科学秀网站观看我们的视频you might want to head on over to YouTube.com/SciShow 观看一系列相关视频 并点击浏览按键to watch a bunch of episodes and also click on that subscribe button. 谢谢Thanks! 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  • 2021-10-17吃早饭真的对减肥有帮助吗?[片头曲♪][INTRO ♪] 早餐是一天中最重要的一餐Breakfast. It’s the most important meal of the day 或者说大家都这样认为or so we’ve been told. 但科学家就这一说法的真实性做过研究But science has tackled whether or not this is really true, 结果不一 有好有坏and the results have been…mixed. 你可能听过这样一种说法One claim you’ve probably heard is 每天坚持吃早饭有助于减肥that eating breakfast every day helps you lose weight, 这确实是有根据的and there’s definitely evidence to support this. 至少在一定程度上是这样At least, to a degree. 2017年 美国心脏病协会回顾了In 2017, the American Heart Association reviewed 不同饮食模式的影响的相关研究the science on the effects of different eating patterns, 在资料库中查阅相关资料searching databases for relevant studies 寻找其研究结果中的重要模式and looking for big patterns in their findings. 他们得出结论And they concluded that 吃早餐的人患临床性肥胖症的几率更小people who eat breakfast are less likely to be clinically obese. 所以你看 没错吧!So there you go! 但是… 很多研究仅仅只是在But a lot of the studies this was based on 询问人们一些与饮食习惯just asked people to report their breakfast habits 或各种个人信息相关的问题along with various other information about themselves. 缺少实验数据Without experimental data, 很多因素可能会影响研究结论there could be lots of other factors at play, 比如说 不吃早餐的人往往不爱运动like, maybe people who skip breakfast also tend to be less active, 或者饮食不合理or to eat poorer diets overall. 当研究人员真正做了实验后When researchers actually do experiments, 吃早餐的好处就显得没那么明显了the benefits of breakfast become less clear. 例如 2016年For example, in 2016, 研究人员给23个体质指数为肥胖的人researchers randomly assigned 23 people whose body mass indexes 随机分配任务: 连续6周吃或不吃早餐were in the obese range to either eat breakfast or not for 6 weeks. 他们没有明确规定第一组吃什么They didn’t standardize exactly what the first group had to eat, 但规定必须在11点前摄入700卡路里but it had to be at least 700 calories before 11AM. 尽管如此 他们并没有发现Regardless, the researchers didn’t find any difference 两组人员的体重变化在此期间有任何差异between the two groups in their weight change during that time. 其他研究结果也各有不同And other studies have been kind of a mixed bag. 所以 即便很多减肥网站都说So it’s hard to tell if breakfast 吃早餐肯定能在某一方面保证减肥效果has a guaranteed effect on weight one way or another, 但这种说法是否正确还很难说despite what lots of diet websites like to say. 但是 嘿 也不要不吃早餐But hey, don’t give up on breakfast just yet. 它的潜在好处不仅仅是减肥而已Weight loss isn’t the only potential benefit. 美国心脏病协会发布的同一份报告中指出That same American Heart Association report found 吃早餐的人患胆固醇、that people who ate breakfast were less likely to have high cholesterol 高血压或血糖类疾病的可能性更小or high blood pressure or problems with their blood sugar. 2016年的那个实验也发现Even that 2016 experiment found 6周过后 吃早餐的那组人的胰岛素敏感度that the group assigned to eat breakfast had increased insulin sensitivity 有所增强at the end of the six weeks. 他们调节血糖所需的胰岛素减少They needed less insulin in order to regulate their blood sugar, 这一变化是好的which is a good thing. 现在 我们还不清楚为何吃早餐会有这样的效果Right now, why eating breakfast would have these effects isn’t totally clear, 但是不吃早餐的人可能会but it’s possible that people who skip it end up 在之后吃得更多 而这会影响到他们的健康indulging more later in the day, which can affect their health. 除了减肥和健康Outside of weight loss and general health, 学校也极力强调早餐的重要性one place where breakfast also gets a lot of emphasis is in schools. 学生营养早餐项目之所以大受欢迎School breakfast programs are popular 是因为我们希望这个项目能让孩子学习更好because we hope that they’ll help kids do better academically, 但即便是这个项目 其根据也很复杂but even for this, the evidence is mixed. 2009年一项学生营养早餐项目研究报告指出A 2009 review of studies of school breakfast programs found 这个项目对提高学生学习成绩有正面作用that they can have a positive effect on academic performance, 但有一部分的原因可能是but that this may be partly just because 它提高了学生的课堂出席率they encourage kids to actually show up. 而且 无需惊讶And — no surprise here — 这个项目对营养不良的学生来说the benefits of school breakfasts are greater 会有更多好处for kids whose overall nutrition is poorer. 另一组研究人员Another group of researchers took a look 查看了2013年的报告at the evidence out there in 2013, 他们发现 养成吃早餐的习惯确实and they concluded that habitually eating breakfast did 有利于学生在学校集中注意力 提高学习成绩help children stay on task in school and improved academic performance. 但是他们也再次提醒But again, they cautioned 也可能是混入的其他因素造成的影响that other factors could be getting mixed up in this, 比如社会经济地位 吃早餐的孩子的家庭like socio-economic status, kids who eat breakfast may also 可能更有能力为他们提供全面的营养come from families that are better able to provide for them overall. 同样 问题是Again, the problem is that 这些研究很多都没有做过实验a lot of these studies aren’t experimental. 只是把吃早餐They’re just comparing kids 和不吃早餐的孩子做了比较who already don’t eat breakfast with those that do. 这就使我们能得出的结论十分有限This limits how much they can actually tell us. 比如 2015年英国一项研究For example, a 2015 study in Great Britain 让292名11-13岁的孩子had 292 kids between the ages of 11 and 13 填一份早餐习惯调查问卷fill out a questionnaire on their breakfast habits. 他们得出的结论是 孩子是否吃早餐And they didn’t find any relationship between kids’breakfast consumption 与他们认知推理能力的测试分数无关and their scores on a test of their cognitive reasoning ability. 实际做实验的话可以澄清这一点Some actual experiments would help clear this up, 但是 让想吃早餐的孩子不要吃早餐but it’s also not a great idea 并不是一个好主意to deprive kids of breakfast if they want to eat it, 所以现在我们只能利用现有资料进行研究so for now, we’ll have to work with what we have. 如果你想知道早餐对于成年人的影响Also, if you’re wondering what this all means for adults — 吃早餐能否提高工作效率whether breakfast improves our performance at work — 很遗憾地告诉你 相关研究不多well, sadly, this hasn’t been studied very much. 成年人的工作场所和学校不同Unlike schools, adults’workplaces generally aren’t 不会有早餐提供in the business of feeding them and 也不会有人给你打出一目了然的分数don’t usually hand out easy-to-interpret test scores, 所以数据获取可能会更有难度so data is probably harder to come by. 所以我们今天学到了什么?So what’s the takeaway here? 如果你有吃早餐的习惯If you’re the kind of person who eats breakfast, 你可能是个有能力照顾好自己chances are you’re also already someone who has the resources 且营养全面的人to take good care of yourself and eats well overall. 所以 如果你没有这个习惯的话So just starting your day 试着吃一顿丰盛的早餐来开启崭新的一天with a hearty breakfast, if you don’t already, 虽然这不会奇迹般地帮你解决生活中的所有难题won’t magically fix everything that’s wrong with your life. 但也肯定不会对你有害But it definitely won’t hurt you, either. 而且还很可能改善你的健康状况And it might even improve your health. 感谢收看这集《科学秀》!Thanks for watching this episode of SciShow! 营养研究是一门复杂的学科Nutrition research is complicated, 仍有许多东西需要我们研究揣摩and there’s a lot out there to figure out, 比如糖分和脂肪like the deal with sugar and fat. 很多人都说它们很恐怖Lots of people like to say how horrible one or the other is, 但它们到底是如何影响我们的健康的呢?but how do they actually affect your health? 观看《科学秀》了解更多相关知识You can learn more in our episode all about it. 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  • 2021-10-17小行星,系外卫星,以及对卫星的着迷超新星 黑洞 系外行星我们对它们是如此的着迷Supernovas, black holes, exoplanets. We’re fascinated with them, and who can blame us? 以至于有时我们会忽略了对了解宇宙至关重要的But sometimes we forget to talk about the littler things out there like asteroids and 小行星和卫星事实上 探索小天体可能是moons which are critical to our understanding of the universe. The fact is, exploring small 探索太阳系起源寻找太空适宜居住地stuff might be the key to some of our greatest missions in space, like discovering the origins 以及探索资源丰富天体这些航天任务中的关键一环of the solar system, finding habitability and locating resources for future space travel. 那么这周我将给各位讲解三则研究太空天体的新闻So this week, I bring you news from three missions dedicated to studying the little 我是主持人Caitlin Hofmeister欢迎收看SciShow太空新闻guys of space. I’m Caitlin Hofmeister and welcome to SciShow Space News. (简介)(Intro) 上周 NASA开始制造一架用来取样小行星的航天器Last week, NASA officially began construction on its first spacecraft designed to sample 这被称作OSIRIS-REx的任务将计划前往一直径500米的小行星的近地轨道an asteroid. The mission, called OSIRIS-REx, will travel to a 500 meter-wide asteroid in 并采样带回地球 目标小行星将是near-Earth orbit and steal a quick scoop of it to bring back to Earth. Its target will Bennu星 一个可追溯到诞生之日已有45亿岁的时间胶囊be the asteroid Bennu, a 4.5 billion year old time capsule dating back to the creation NASA希望通过对Bennu岩石的化学分析可以回答在太阳系形成之时of the solar system. NASA’s hoping that Bennu’s chemistry will answer a lot of questions 水和有机分子这类生命基石是否存在的问题like whether water and organic molecules, the building blocks of life, were present 除此之外 在我们开始寻找小行星作为后续太空任务的空间站之后at the time of the solar system’s formation. Plus, finding water on Bennu would be incredibly 在Bennu上寻找水资源将会变得非常容易handy as we begin to look to asteroids as possible way stations for future space missions, 除此以外我们还可能找到大量烙铁 镍 钛等材料and we might find a wealth of materials like iron, nickel or titanium to boot. OSIRIS-REx OSIRIS-REx计划估计会在2019年的九月启动并在两年后进入绕Bennu轨道will launch in September of 2016 and it’ll enter orbit around Bennu two years later. 然后使用三种分光仪扫描Bennu表面并确定Bennu的化学元素构成Then it’ll begin scanning its surface with three spectrometers to determine its chemical Bennu上的引力场比地球的小所以太空船不可能着陆composition. Bennu’s gravity is much lower than that of Earth’s, so the craft won’t 因此在2019年之前会选择一个最佳点采集一些小行星土壤be able to land. So by 2019 it’ll choose the perfect point to snatch up some asteroid 通过使用一种名称挺喜庆的仪器叫“碰下走样本采集仪”dust using a delightfully named instrument called a Touch-And-Go Sample Acquisition Mechanism, 简称TAGSAM 然后这个太空船会快速返航把岩石样品带回地球or TAGSAM. Then the little craft will hightail it back to Earth, releasing its sample return 飞行器应该是在2023年返回地球capsule which should arrive in 2023. 现在看看离家更远的太空新闻在塔斯马尼亚岛和新西兰的天文学家Now looking at space news much farther from home, astronomers in New Zealand and Tasmania 声称上周他们观测到一颗新的外卫星said last week that they’ve observed what they think is the first known exomoon, that 这是个环绕外行星的卫星然而在细节上还比较粗略 粗略到is, a moon orbiting an exoplanet. Details, however, are kind of sketchy, like so sketchy 天文学家说他们可能弄错了他们本认为自己可以看到that the astronomers say they might be wrong. They think they could’ve seen either an 外行星和一个卫星或是环绕一个又小又暗的恒星的行星 但不管怎样exoplanet with a moon or a small, dim star being orbited by a planet. But either way, 他们的观测是为未来发现外卫星的一大步外卫星的确是their observation was a big step toward finding exomoons in the future. Exomoons are really 难以发现的 因为它们又小又暗小型外行星几乎是hard to find because they’re so small and faint. Even small exoplanets can be nearly 不可能找到的 因为它们被耀眼的恒星掩藏了但有一种方法叫做impossible to spot because they get lost in the glare of their stars. But a method called 引力透镜 将其与好的计划相结合也许能让我们观测到遥远的卫星gravitational lensing combined with good planning may allow us to observe distant moons in the 在未来 通过引力透镜法一个巨大的天体能作为极佳的透镜future. With gravitational lensing, a massive body in space can act as a really good lens 光能从它的后面穿过大气层这种神秘的for light that passes through its atmosphere from behind. That’s how this mysterious 天体将首先被发现更大的天体将放大微弱恒星的光body was spotted in the first place. The larger body magnified light from a distant star, 然后从这个角度能看到大气层后的小天体但是更大的天体可能也and in that light the astronomers saw a smaller body. But the bigger body could’ve either 已形成了行星或非常微弱的恒星或是它们比天文学家们设想的还要远been a planet or a very dim star of its own that’s actually farther away than they thought. 如果我们一旦知道它有多远我们就几乎可以确定它的存在了 就像优秀的科学家一样If only we knew how far away it was we’d be able to tell for sure. So like good scientists, 天文学家们准备再试一次使用两座遥远的望远镜进行技术修正the astronomers are gearing up to try it again. Using two distant telescopes fixed on the 在相同地点观测相同的透镜影响他们计算天体确定的距离same point and observing the same lensing effect, they plan to triangulate the distance 并测量出它的大小这个叫做视差的简单解决方法to the body and figure out how big it is. It’s a simple solution called parallax that’s 对于我们而言在一世纪内都适用而且这也许是发现外卫星的关键served us well for more than a century, and it just maybe the key to discovering exomoons 我们对未来充满信心with confidence in the future. 最终 另一个卫星任务将画上句号上周 NASA声称他们期望And finally, another moon mission is drawing to an end. Last week, NASA said it expects 四月21日星期一著名航空器月球气尘检测器将能登陆月球the spacecraft known as LADEE to crash into the surface of the moon this Monday, April 十一月始 月球气尘检测器又称月球大气与粉尘环境21st. Since November, LADEE, also known as the Lunar Atmosphere and Dust Environment 探索者 将收集月球大气的图像与测量数据并且现在准备Explorer, has been collecting photos and measurements of the lunar atmosphere and now is ready to 某一天调用它 也许要运行140天或更久在地球密度的一百万亿倍的状态下call it a day, or rather 140 or so days. At 100 trillionth of the density of the Earth’s, 月球大气可能就像其它的卫星 小行星一样了the lunar atmosphere is probably like that of many other moons, small planets, and asteroids. 所以月尘器已经观察了发送大量的数据传回地球以供分析 最显著的是So LADEE has been observing away sending loads of data back to Earth for analysis. Most notably, 似乎解释了日出时奇怪的神秘彩色辉光那是1970年代阿波罗it seems to have solved the mystery of the strange streaky glow at sunrise that Apollo 宇航员报告说观测到的 根据月尘器的观测这归因于astronauts reported seeing in the 1970s. According to LADEE’s observations, it was caused by 我们甚至还不太确定的机载月球尘埃月尘器真是个好孩子 感谢你airborne lunar dust that we weren’t even sure was there. Good boy LADEE, thank you 这完美的六个月for a good six months. 感谢收看太空科学秀 尤其是Subbable的订阅者And thank you for watching SciShow Space News, especially to our Subbable subscribers. Fancy 想要得到我们节目特制的领带和巧克力棒吗?赶快登陆subbable.com/scishow了解得到它们的方法a SciShow tie or a sciency chocolate bar? Then go to subbable.com/scishow to learn how 如果你对我们的节目有任何问题或想法to get one. And if you have any questions or ideas for an episode you’d like to see, 可以在我们的脸书和推特评论区留言如果你想和我们一起进步 关注我们的youtube.com/scishowspaceyou can find us on Facebook and Twitter and, as always, in the comments below. And if youwant to keep getting smarter with us, just go to youtube.com/scishowspace and subscribe.
  • 2021-10-17你能燃烧金属吗?[开始主题曲][intro theme] 我们都知道你能将金属充分加热使它融化或折叠So we all know that you can get metal hot enough to melt and fold 或者将它锤成一米长的双刃宽剑or be hammered into meter-long double-edged claymores 但是你真的能燃烧它们吗but can you actually burn it? 你可能从金属最常见的形态了解它们You probably know metals from their most familiar forms 金戒指 壁炉拨火棍 汽水罐a gold ring, a fireplace poker, a soda pop can 但是金属其实有很多种but metals are actually a pretty diverse group. 事实上 它们构成了元素周期表中的大部分元素In fact, they make up most of the elements in the periodic table. 我们一般根据相关联的物理性质定义金属Metals are generally defined by the physical traits we associate with them 它们都很硬 但具有可塑性 这意味着它们能被锤成薄片they’re hard but malleable, meaning they can be hammered into thin sheets, but 但它们也有延展性 可以被拉成电线they’re also ductile or can be pulled into wires. 但也许它们最重要且最著名的特性是 它们是电和热的良导体But probably their most important and well-known property is that they’re awesome conductors of heat and electricity. 它们大都是银白色 有光泽的They’re also generally gray and shiny. 它们能作为电的良导体 主要上是因为它们中的一些能够燃烧And the reason they’re so good at conducting electricity is basically the same reason that some of them can burn. 大多数金属的原子很容易失去电子 所以当热或电穿过一片金属时Atoms in most metals tend to give up electrons really easily, so when heat or electricity run through a piece of metal 那基本上是一股活跃的电子 然后当它们燃烧时that’s basically a stream of excited electrons. And when they burn 金属放弃了一些电子 但是这个过程并不总是像你想象的那样metals are giving up some of their electrons. But the process doesn’t always look like you might imagine. 例如 一大块纯铁不能长时间保持它的纯度A hunk of pure iron, for example, doesn’t tend to stay pure for very long. 这是因为 那些铁原子真的很想和氧私奔That’s because those iron atoms really wanna hang out with oxygen. 氧气喜欢电子 对带走铁急切想交出的珍贵的电子 感到非常开心Oxygen loves electrons, and is more than happy to take up all the precious electrons that iron is eager to surrender. 所以 当暴露在氧气里时 无论是在空气中还是水中So, when exposed to oxygen either in air or water 铁会生锈并且变成氧化铁the iron rusts and becomes iron oxide. 这和燃烧有什么关系呢What does that have to do with burning? 这是一种叫做氧化的化学反应Well that is a chemical reaction called oxidation. 燃烧也是氧化 只是快得多Burning is also oxidation, just much faster 所以 生锈也是一种燃烧so rusting is a kind of burning 实际上 它的确产生了少许热量 只是非常缓慢 也没有点燃任何东西it actually does give off a little bit of heat, it’s just very slow and doesn’t actually ignite anything 但是在特定情况下 铁是可以点燃的 铁越热 或者任何一种金属变得but iron can ignite under the right circumstances. The hotter the iron, or really any metal gets 和氧气的关系更密切the greater its affinity for oxygen becomes. 所以 如果你有足够小足够热的金属块 它会达到一个让它发生剧烈氧化的燃点So if you get small enough pieces of it hot enough, it’ll reach a point where it undergoes what’s basically very rapid oxidation. 这个点就是能点燃它的温度This point is its ignition temperature. 你可以在家里尝试!你只需要一些精钢丝 钳子You can try it at home! All you need is some extra fine steel wool, some pliers, 一个打火机之类的 能点火的东西and like a lighter or something that makes fire, 一个你能放置热金属薄片的容器and something that you can catch the hot flakes of metal in 好让它们不掉在你的柜台上 把你的房子烧着 当心so that they don’t fall on your counter and catch your house on fire. Be careful. 钢丝大概就是削得很细的金属 大部分是铁 并且This steel wool is basically just thinly shaved metal that’s mostly iron, and 更精纯 金属的接触面越大 越容易燃烧the more fine, the more surface area the metal has, the easier it is to burn. 来看看我们怎么实现这个Let’s see if we can make this happen. 哇 这很漂亮Oh wow, that’s pretty! 做到了!IT WORKS! 它有没有伤到我的脸 弄得有点痛呢 有And did it hit me in the face with a little bit of pain? Yes! 所以为什么钢丝会烧着 但布鲁克林大桥不会So why will steel wool burn but not the Brooklyn bridge? 一个铁铸煎锅也不会 好吧,因为一些原因Or a cast iron skillet? Well, for a few good reasons 首先因为金属是这么优秀的热导体first because metal is such an excellent heat conductor 它传递作用于它的热量 这更难让它的某个特定部分达到燃点温度it disperses heat that’s applied to it, which makes it harder for any particular part of it to reach its ignition temperature. 把一个煎锅放在火上 热量会很快分散到整个金属上Put a skillet on a flame, and the heat quickly disperses through all of the metal 于是表面的温度并没有高到 可以支撑一个 让整个锅烧着的反应so the surface doesn’t get hot enough to sustain a reaction that would actually set the whole skillet on fire. 但是那些小钢丝线那么细 以至于没有可以传递热量的余地But those tiny little threads of steel wool are so thin that there isn’t any room for the heat to spread out 所以铁丝很快就达到燃点so the iron quickly reaches its ignition temperature. 第二个主要因素和接触面有关A second major factor has to do with surface area. 这个锅的大部分铁都在锅内部Most of the iron in this skillet is inside the skillet. 不能和空气接触It doesn’t come into contact with the air. 钢丝烧得很快 因为这些长线有更大接触面暴露(在空气中)Steel wool burns because these long strands have huge surface areas that are exposed 准备与空气中的氧发生反应and ready to react with the oxygen in the air. 这就像一张纸很容易烧着 但是一个大的旧木头却很难做到It’s like a piece of paper is super easy to light on fire, but a big ol’ log is hard to get going.. 铁屑会燃烧 铁棒却不会Iron filings will burn, iron rods will not. 最后 这也是一个很好的提醒 (提醒我们)所有东西 无论发不发生反应 是怎样烧成微粒的In the end it’s a good reminder of how everything boils down to particles either reacting or not reacting. 如果你把金属形象化为铁铸煎锅 你只能看见它转移火焰 却永远不会真正烧着When you visualize metal as a cast iron skillet, you only see it deflecting flames and never actually burning 但如果你在它的元素状况上思考 并回想铁和许多其他金属but if you think of it in its elemental state and remember how iron and many other metals 对氧有着怎样大且久的迷恋 这会拓宽你对 几乎所有事情的理解have big ol’ crushes on oxygen, it’ll broaden your understanding of — pretty much everything. 感谢您收看本集SciShow 也感谢我们Subbable的订阅者让这期节目成为可能Thank you for watching this episode of SciShow, and thank you to our Subbable subscribers for making this possible. 如果您有任何问题 评论 或建议给我们 我们会在Facebook和Twitter上处理评论If you have any questions or comments or suggestions for us, we’re on Facebook and Twitter and down in the comments below 如果你想和我们Scishow一起变得更聪明 你可以去youtube.com/scishow订阅(我们的节目)and if you wanna keep getting smarter with us here at SciShow, you can go to youtube.com/scishow and subscribe. 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  • 2021-10-17成为一名探险科学家我和Squeaks 刚刚远足回来Squeaks and I are just getting back from a hike! 我们露营的地方有特别多的不同种类的鸟类 植物 和岩石Where we live, there are tons of different kinds of birds, plants, and rocks — so many 多的简直没法走路了that it’s hard to keep track of them all! 所以我和Squeaks用了一种特殊的工具来帮助我们完成探险 它就是野外日志So Squeaks and I use a special tool to help us record our discoveries: a field journal! 野外日志是科学家们所使用的一种特殊工具 用于A field journal is a special kind of notebook that scientists use when they’re working 在野外工作时使用outside. 他们用它来记录所见到的东西的重要特征They use it to record important facts about the things they see out in the world, and 和他们对于所看到的东西的自己的想法their own thoughts and questions about what they’re seeing. 你也可以用野外日志来做同样的事情And you can use a field journal to do the same thing! 如果你所在的地方是春天 就像这 或许你能看到许多If it’s spring where you live, like it is here, maybe you’ve started to see lots of 花朵flowers. 你可以用你的野外日志来了解你周围的花朵You can use your field journal to get to know the flowers in your neighborhood! 你的野外日记是你可以写任何东西的地方 代替了笔记本 便利贴 或者只是Your field journal can be anything you can write in: a notebook, a binder, or even just 几张钉在一起的纸a few pieces of paper stapled together. 当你准备好研究花朵的时候 拿出你的野外日志 几支铅笔When you’re ready to study the flowers, just grab your field journal, some pencils 蜡笔 还有一个成年人and crayons, and a grown-up. 然后 去外面找尽可能多的花吧Then, head outside to find as many flowers as you can! 当你首次外出的时候 确保要写上日期再带上一个成年人When you first get outside, be sure to write down the date, or have a grown-up do it for 然后再记录一下天气you, and then make some notes about the weather. 是热呢还是冷呢Is it hot or cold outside? 最近下雨了么Has it rained recently? 然后 找一朵花 仔细观察它吧Then, find a flower and examine it carefully. 问你自己一些问题 比如:这朵花长在哪里呀Ask yourself questions like: where is the flower growing? 生长在什么样的土壤里呢What kind of soil is it in? 那个区域光照充足么Is there a lot of sunlight in that spot? 花朵旁边有虫子么Are there bugs hanging out around the flower? 写下一切你观察花时看到的和想到的Write down everything you see and think about when you’re looking at the flower in your 把它们都写在野外日志里field journal. 下面来到好玩的环节了 把你看到的画下来Next comes the fun part: draw what you see! 科学家们非常认真仔细的作画以便记录Scientists make very careful field drawings to help keep track of every detail of what 他们研究的所有细节they’re studying. 你可以画下不同的花瓣和叶子 展示一下它有多大You can draw the different petals and leaves on the flower, and show how big it is. 你越认真的观察和作画 你越能更好的了解每一种花The more carefully you look and draw, the better you’ll get to know each flower! 你做完画以后就可以研究下一朵花了When you’re done drawing, you can choose another flower to study next. 当你研究完好几种花的时候 你就可以休息一下了Once you’ve studied a few flowers, you can be done for the day! 既然你已经做了野外日志 你就可以通过查阅它来Now that you’ve started your field journal, you can come back to look at the flowers again 在明天或者几天后再次观察花了tomorrow, or even in a few days. 然后做同样的事情:写下你看到的东西 比如花朵是否Then do the same thing: write down things you see, like whether the flower is getting 有充分光照 是否周围有虫子lots of sunlight, or if there are bugs flying around. 然后在画一张图And draw another picture of it! 过一段时间 你就能看到花朵是如何变化的了 比如是否Over time, you’ll be able to see how the flower is changing — like if it grows more 在雨后长的更加茁壮了after it rains a lot. 这就是科学家保存野外日志的原因That’s why scientists keep field journals! 所以他们能记得他们学会了什么 还能通过查阅笔记来了解So they can remember the things they learn, and look through their notes to see how things 事物经过时间洗礼如何变化change over time. 你可以用你的野外日志去研究更多东西 不仅仅是花And you can use your field journal to study more than just flowers! 比如 如果你周围有很多鸟 你可以用你的野外日志来For example, if there are lots of birds around, you can use your field journal to keep track 记录它们of them, too! 当你在研究鸟类或者其他动物的时候你可以注意一下When you’re studying birds and other animals, you can pay attention to things like what 你看到它们的时间 它们是单独行动还是成群结队 它们的声音是什么样的time of day you see them, if they’re alone or in groups, what sounds they make, and what 它们吃什么they’re eating! 啊 你说的对SqueaksAh, you’re right Squeaks! 我们还没说到写野外日志最棒的地方呢We haven’t even talked about one of the best parts of having a field journal! 你可以装饰它You can decorate it! 你可以像我们一样用超酷的贴纸和画装饰它You can cover it in cool stickers and drawings like we have! 你有想要和我们分享的超酷野外日志吗Do you have a super cool field journal that you’d like to share with us? 我们很高兴见到它We’d love to see it! 找一个大人 给我们发邮件吧 地址是kids@scishow.comGrab a grownup and send us an email at kids@scishow.com. 感谢谷歌科技赞助我们完成这一期视频We’d like to give a big thanks to Google Making Science for helping us make this episode! 谢谢 下次再见Thanks, and we’ll see you next time here at the Fort!
  • 2021-10-17为什么草坪必须消失In 2015, 75-year old Gerry Suttle was sitting on her porch2015年 75岁的Gerry Suttle正坐在家的门廊里 watching the leaves rustle in the trees观察树上的树叶沙沙作响 when a cop rolled up and handed her an arrest warrant.这时一个警察出现了 并向她出示了拘捕令 The reason for her arrest?她为什么被逮捕呢? She had failed to mow her lawn.因为她没有修剪草坪 That’s right.是的 The cops and Suttle’s neighbors deemed it necessary警察和Suttle的邻居一致认为 to hold the threat of arrest over this septuagenarian有必要逮捕这位七旬老人 because the turf grass occupying the space in front of her house因为她门前的草坪 was left unchecked.没有修剪 How did we in the United States come to this?在美国为什么会这样呢? Why is the lawn such a sacred space in white suburban America?为什么美国白人郊区的草坪是如此神圣的空间? This is the story of the American lawn.这是美国草坪的故事 How it came to be,美国草坪是如何形成的 the complex underpinnings of its green blades,绿地后复杂的背景是怎样的 and how we might work to rid ourselves from its cultural grasp.以及我们如何努力摆脱它的文化束缚 This video is sponsored by CuriosityStream,这则视频由CutiosityStream赞助 which now comes with Nebula for free如果你点击详情页的链接注册 when you sign up using the link in the description.CuriosityStream和Nebula都可以免费使用 第一章 草坪简史 In the 17th and 18th century, landholding在17 18世纪时 European aristocrats were getting jealous.持有土地的欧洲贵族变得嫉妒 They saw beautiful fields of grass他们看到自己最喜欢的画家的绘画中 and perfectly trimmed patches of green in the paintings漂亮的草地和修建完美的小块草坪 of their favorite artists and wanted all of it for themselves.他们想自己也拥有这样的草坪 So, they began to terraform their world.所以他们开始修整自己的世界 With the enclosure of common land,伴随着公用土地被征用 aristocrats gained prime property for lawns贵族们获得了占有草坪的优先特权 and forced lower class peasants into wage labor jobs他们强迫下层阶级的农民做一些管家和园丁之类 like groundskeepers and gardeners.付薪劳动工作 From France, to Italy, to England从法国 到意大利 再到英格兰 the wealthy ruling class embraced the luxuries of turf grass富裕的统治阶级坐拥广阔的草坪 and used it as a foundational element并将之作为一项基础元素 in landscaping design for their manors.用于庄园的景观设计中 And what could be more a display of capitalist power, of leisure, and of wealth还有什么比这更能展现资本家的权力 闲情和财富呢? than a field of green that had to be closely watched and tended by former peasants这些因为圈地被迫成为劳工的农民 forced into wage labour through land enclosures.悉心照料着的草地 Along was a way for these English elites to show off that they were so wealthy正是这些英国贵族炫耀财富的方式 that they didn’t need their land to grow food.他们根本不需要用他们的土地种食物 That’s author of Lawn People, Paul Robbins, on the podcast 99% Invisible.这是Lawn People的作者Paul Robbins在播客 99%Invisible的发言 He goes on to add that the English ruling class used lawns to show他继续讲到 英国统治阶级利用草坪彰显 that “they could afford to let their fields go fallow,他们可以负担得起土地休耕 and could afford to keep grazing animals and负担得起放牧 and syc the wielding peasants to keep it short负担得起让农民割草 So the lawn began as a display of wealth for the white European aristocracy所以草坪开始成为欧洲白人贵族阶级财富的象征 but then was quickly exported to the colonial project that is the United States.但这种风气很快扩散到了当时是殖民地的美国 Thomas Jefferson and George Washington enjoyed托马斯杰弗森和乔治华盛顿都喜欢 wide manicured lawns kept perfectly trimmed修整完美的广阔草坪 by the forced labor of enslaved people.尽管这是强迫奴隶的结果 But it wasn’t until the 1870s,但是直到十九世纪七十年代 when the push lawn mower, the sprinkler, and the suburbs随着手推除草机 洒水器和郊区的发展 all sprouted into the American lifestyle that the lawn became a reality草坪才迅速在统治阶级以外的人群中成为现实 among those outside the ruling class.并成为全美国的生活方式 Having already been established as a symbol of luxury and leisure,自从草坪已经成为财富和休闲的象征 the lawn was adopted in the outskirts of cities草坪也被城市边缘地区的人接受 and soon turned into a symbol of conformity.并迅速成为共识的象征 Through advertisement after advertisement,随着源源不断的广告 and eventually neighborhood codes and laws,以及社区公约的最终达成 a patch of grass in front your house房前一片草坪 became a staple in the image of the American dream.成为美国梦的实体意象 But in the 100 years following the Civil War但是在内战后的一百年里 the lawn was only slowly taking up space.草坪的地位只是缓慢提高 After World War II, however,然而 二战后 the adoption of the American lawn exploded.人们对草坪的接受度飙升 Soldiers came home from war,二战军人返乡 suburban sprawl accelerated at an astronomical pace郊区以极快的速度蔓延 and the chemicals used in the trenches战争里使用的化学剂 now found their way onto plants and insects.在除草杀虫上发挥了新的作用 With the suburban boom came the boom in lawn culture.伴随着郊区潮 草坪文化的浪潮也接踵而至 We even see this in the deluge of lawn ads in magazines around that time period.当时杂志上泛滥的草坪广告足以说明 With thousands of Americans now proud owners of lawns,随着成千上万的美国人成为自豪的草坪主 chemicals of war rebranded themselves战争时期的化学剂 into pesticides and herbicides to keep the grass green.也重新应用在使草坪常绿的杀虫剂和除草剂中 And by the 1960s, this chemical warfare got so bad到了20世纪60年代 化学剂的泛滥 that Rachel Carson noticed the death of birds all around her,使蕾切尔·卡逊注意到周围鸟类的死亡 prompting her to write Silent Spring.这促使她写出了《寂静的春天》一书 But those that predominantly benefited但战后政府计划 from the generous post-WWII government programs诸如《退伍军人法》 like the GI Bill and guaranteed home loans和引发草坪热的担保家庭贷款 that fueled the adoption of the lawn were white.最主要的受益者是白人 In short, the suburban lawn was very much a white American reality.简单来说 郊区草坪基本上就是属于美国白人 In fact, throughout its transformation and expansion实际上 随着草坪的转变和发展 the monoculture suburban lawn worked这种单一文化的郊区草坪 in tandem with its owners to crowd out any plant, animal, or human和它们的主人一起排斥着 that didn’t fit within their definition of beauty, conformity, or civilization.那些不符合他们对美 和谐 或文明的定义的动植物或人类 第二章 草坪曾是(也仍然是)殖民主义的工具 The lawn quite literally allowed rich white American colonists草坪很大程度上使得美国富裕的白人殖民者 and then middle class suburban whites还有郊区中产阶级白人 to physically enact colonization of the land在事实上施行土地殖民 While indigenous genocide raged当对土著的屠杀肆虐时 cows brought from Europe ravenously ate the native varieties of grasses从欧洲带来的牛在美国本土大肆吃掉了各样的草 but colonists quickly realized但殖民者很快意识到 their cattle were unsuitable for the American terrain他们的牛并不适合美国的地理环境 The European cows just couldn’t get enough nutrients from native grasses.欧洲牛无法从美国当地的草里得到足够营养 So, the colonists brought Europe to the Americas所以 殖民者把欧洲的习惯带给了美洲人 and planted the seeds of European grasses种下了欧洲的草种 which sprouted out of the ground这些种子生根发芽 and pushed out native prairie, plants and animals.占领了本土的草地 挤走了植物和动物 In short, the origins of American turf grass are rooted in总的来说 美国草坪的起源植根于 the colonial terraforming of indigenous land,本土土地的殖民改造 an act which, in a small way, legitimized the wholesale theft of land这种行为使得大规模土地窃取在欧洲白人心中悄然变得合法化 in the minds of white Europeans because it now looked much more like因为现在的美国草坪 the European countryside they were used to.和欧洲白人曾经住的农村没什么两样 Much in the same way the United States massacred the buffalo,无独有偶 美国当时屠杀水牛 a staple food source highly important to indigenous plains nations,这在当地平原国家是很重要的食物来源 as well as forced the assimilation of thousands of indigenous children殖民者还强制性同化数千名 at violent boarding schools野蛮寄宿学校里的儿童 that quite literally tried to beat any cultural or linguistic heritage out of them极力试图打压任何异于他们的文化或语言的传承 so too did they use European grass varieties like Kentucky Bluegrass,他们还利用各种各样欧洲草地 如肯塔基蓝草 to transform their landscape into one把这片土地变成 that fit their white European vision of the world.符合欧洲白人世界观的样子 But the lawn is not only wielded as a tool of cultural destruction但草坪不仅仅充当了文化摧残的工具 it is also fueling multiple environmental crises.还是各种环境危机的加速器 Now, in the midst of droughts and the climate crisis,如今 在干旱和气候危机之下 turf grass lawns are starting to look a lot less appealing to own草坪开始失去魅力 人们已不愿拥有 let alone spend time to manicure.更别说花时间打理 In the United States, the emissions from lawn maintenance equipment like gas-powered mowers在美国 像燃气割草机这类草坪维护装备的排放量 account for 4% of the country’s total annual carbon emissions.占全国二氧化碳排放总量的4% This number is so large这个数目如此庞大 because turf grass is the largest crop by area in the United States因为草坪是美国面积最大的作物 Lawns occupy 40 million acres of land in the United States草坪在美国的面积占到了四千万公顷 which is roughly three times the area of America’s second biggest crop: corn.约是美国第二大农作物玉米面积的三倍 And all of this grass requires a massive amount of water as well.而且这些草地还需要大量水 Every single day, U.S. lawn owners每一天 美国的草坪主人 collectively pour 9 billion gallons of freshwater总共要浇九十亿加仑的水 onto their lawns to keep them green.以维持草坪的鲜绿 A lot of this water often hits sidewalks or roads,很多水浇到了路上 rarely making it into the roots of plants很少能渗到草的根部去 and often running off into local waterways,而且经常会流进下水道 carrying all the chemicals that American lawn owners’ use on their grass.草坪主用来滋养草坪的化学剂也一同流走了 According to the EPA, lawn owners douse their lawns环境保护局的资料显示 草坪主们每年在草坪上 with 78 million pounds of pesticides喷洒七千八百万磅杀虫剂 and 90 million pounds of fertilizer every single year.用掉九千万磅化肥 Traces of these chemicals are not only ending up in waterways and our drinking water,这些化学剂不仅仅流向下水道和我们的饮用水 but they’re shredding animal and insect populations like the monarch butterfly.还使像王蝶这样的动物和昆虫的数量减少 And these chemicals are not only harmful to plants and insects,化学剂不仅对植物和昆虫有害 some lawn care equipment like RoundUp一些草坪护理用品比如农达除草剂 has been linked to cancer in a number of its human users.已经被发现和一众人类使用者患癌有关 We are quite literally ravaging the planet and ourselves to maintain我们为了保护房前那一小片绿色 a little patch of green in front of our houses.实在是损害了我们的家园和我们自己 And in some cases, like Gerrry Suttle,有些时候 像Gerry Suttle遇到的这样 it’s forced on us by cops and the state.会有警察和政府给我们施压 The lawn, with its history of class, race, and colonial oppression带着有关阶级 种族 殖民压迫的历史 combined with its penchant for ecological destruction, must die.以及破坏生态的倾向 草坪必然消失 But to do that we have to provide real alternatives但为了消除草坪 我们必须有真正的方案 that not only replace the grass below our feet不仅仅是找东西替代脚下的草地 but also repair the harm caused by American capitalist conquest.还需要修复美国资本征服带来的伤害 第四章 没有草坪的未来会怎样 Understanding that lawns are intimately linked with visions of class, settler-colonialism,要知道草坪和阶级 殖民主义 and capitalist ecological destruction还有资本对生态的破坏是紧密联系的 is essential for developing effective and lasting alternatives.理解这一点对提出有效持续的解决方案很重要 If you own a lawn, the simplest thing you could do is to just stop taking care of it.如果你有一片草坪 最简单的就是别再管它了 But I think that this approach should be seen as a last resort.但我觉得这应该被当作下下计 In order to repair the harm caused by centuries of lawn colonization要想修复数百年以来的草坪殖民带来的损害 we need to develop active alternatives.我们需要找到积极的解决方法 Think about what we could do with that 40 million acres of space如果我们把自己从草坪中解放出来 if we rid ourselves of turf grass.想想我们能拿4千万公顷的土地做什么 Front yard gardens with food available to all who want it, native perennials and gardens前院花园里有可以随意采摘的水果 有多年生植物 that actually synthesize with the landscape, xeriscaping in dry climates有综合了观赏园艺和节水型园艺的花园 that don’t require any water to maintain.在气候干旱时 无需任何水的灌溉 These endeavors are already happening,这些努力已经付诸实践 with thousands of backyard farms replacing lawns across the country,全国有数千个后院农场取代了草坪 a recent Southern California incentive paying residents to rip up their lawn,最近南加州发放资金激励市民清楚草坪 or someone like Taylor Keen, one of the Omaha people who’s been developingTaylor Keen 奥马哈市的一位市民 and growing indigenous seed varieties in his lush backyard gardens.在自家繁茂的花园里种上当地的种子 These are the actions we need to take.这才是我们应当采取的做法 Because, to start the process of decolonization因为 要想开始去殖民化进程 and thriving in a zero carbon world,在一个零碳世界里蓬勃发展 the lawn must die.草坪必须消失 If you’re watching this video如果你在看这个视频时 wondering whether there are more people getting arrested想着是不是有更多的人 for not mowing their lawns因为没有除草而被逮捕 or you just want to learn a bit more about the connection或者你只是想了解一些 between lawns and settler colonialism, you’re in luck.草坪和殖民主义的联系 那你来对了 I actually did write an extra section about lawn control and settler colonialism,实际上我确实写了关于草坪管控和殖民主义的其他内容 but it got left on the cutting room floor.但这部分被忘在剪辑室的地板上了 So I’ve uploaded that section所以我上传了那部分内容 as an extended edition of this video on the streaming platform作为这个视频的加长篇 my creator friends and I built called Nebula.放在我和创作者朋友们开发的这个叫Nebula的流媒体平台 The bonus content replaces this ad激励内容代替了广告 because there aren’t any ads on Nebula.因为在Nebula上没有任何广告 And you’ll not only see a lot of extended editions, exclusive content and ad free videos在Nebula上你不仅可以看到许多番外版视频 独家内容 无广告视频 over on Nebula from me, but also from channels like Second Thought and Polymatter.还能浏览像Second Thought和Polymatter这样的频道 Nebula allows viewers to support creators directlyNebula允许观众直接支持创作人 so they don’t have to worry about the pesky YouTube algorithm or financial stability因此他们就不需要担心YouTube繁琐的算法或固定的交易方式 Nebula is awesome but it’s now made even better with our partnership with CuriosityStream.Nebula很赞 现在和Curiosity Stream合作就更完美了 CuriosityStream is the go to streaming platform for thousands of top tier documentaries,Curiosity Stream是集数千部一流纪录片的流媒体平台 like Insect Apocalypse,像《昆虫启示》 which details the recent decline in insect populations across the world.讲述了全世界近期昆虫数量的下降 And because CuriosityStream loves supporting educational creators,由于CuriosityStream热爱支持科普教育类创作者 we worked out a deal where if you sign up with the link below,我们达成共识 点击下方链接注册 not only do you get access to CuriosityStream,你不仅能得到CuriosityStream的权限 but you’ll also get Nebula for FREE.你还可以免费使用Nebula And this is not a trial,这不是试用 you’ll have Nebula as long as you’re a CuriosityStream member.你将得到和CuriosityStream会员同时长的Nebula使用权 And just for this weekend, CuriosityStream is offering a special deal to my viewers这周末CuriosityStream将为我的观众带来特殊优惠 41% off their annual plan年度会员计划的69折 that’s less than a dollar a month for BOTH CuriosityStream and Nebula.意味着每月不到一美元就得到双平台会员 So by signing up, you not only directly support Our Changing Climate,注册后 你不仅直接支持了《气候变化》栏目 but you gain access to thousands of documentaries还可以浏览数千部纪录片 and exclusive videos from your favorite creators和你最喜爱的创作者发布的独家视频 So if you want to support both Our Changing Climate所以如果你想支持本栏目 and hundreds of other educational content creators和许许多多的教育内容创作者 go to CuriosityStream.com/OCC or click the link in the description登录CuriosityStream.com/OCC或者点击详情页链接进行注册 and sign up for CuriosityStream and Nebula for just $11.79 per year,每年只要11.79美元 that’s 41% off.享受69折优惠价 Thanks so much for watching all the way to the end!感谢大家看到最后 If you’ve already signed up for CuriosityStream如果你已经注册了 你也可以通过 you can also support me by becoming an Our Changing Climate Patron.成为 气候变化的赞助人来支持我们 Just pledging one dollar a month gives me the financial stability I need to keep making只需要每月赞助一美元 就可以帮助我有稳定的经济基础 more videos like this.来制作更多这样的视频 Thanks again for watching and I’ll see you in two weeks.再次感谢观看 两周后再见
  • 2021-10-17再版月亮——克鲁特尼小行星的奇妙轨迹Hey Brady, I am Matt Henderson. I like你好啊Brady 我是马特•亨德森 making mathematical animations and I我喜欢制作数学动画 wanted to show a few that relate to the并且想展示一些 patterns of orbits in the solar system.有关太阳系中行星运动轨迹的图案 The first one is the inner planets; and首先展示的是近日行星 so this is the approximate pattern that这是根据近日行星轨迹 the inner planets trace out – obviously制作出的近似模型 things aren’t to scale. We’ve got the Sun,显然这些行星的大小不成比例 we’ve got Mercury, Venus, Earth and Mars这是太阳 这些分别是水星 金星 地球和火星 going around in their approximate orbits它们在近似轨道上以相对速度 and relative speeds. So they’re spinning围绕太阳旋转 around, the Sun is at the centre and now太阳是它们公转的中心 we’re to actually move so we’re现在我们正式开始绘制图案 following Earth. And we’re interested in,我们以地球为参照物 what are the patterns that are traced out by我们对其他行星轨道的 the other planets? From kind of like from图形很感兴趣 the perspective of Earth we start to see以地球为中心点 some interesting patterns.一些有意思的图案开始成形 The pattern from Venus is starting to be金星的运动轨迹 quite regular.开始变得有规律可循 We’ll start to see this kind of我们逐渐发现 five-pointed shape;轨迹开始接近五边形 you can see we’ve got one of the points如你所见 这是其中一个角 here, we’ve got two, three, and the next这里是第二个 第三个 time Venus comes around it completes以此类推 this five points: 1, 2, 3, 4, 5.周而复始 And that’s because the ratio of the这是因为金星和地球 orbits between Venus and Earth are- is in运动轨迹之间的比例 an 8 to 13 ratio so the difference there是8比13 is accounting for the five-fold symmetry.因此这里的差异是因为五重对称 In general it’s just like a pretty pattern.这些轨迹通常会形成美丽的图案 I think these are called epicycloids,我认为这些是外摆线 they’re kind of like the spirograph它们与螺旋形图案 patterns that you get rolling circles有异曲同工之妙 around circles.都是围绕圆圈转圈 And those just happen to be the ones而这些恰好是 that the planets trace out.行星的运动轨迹 Now let’s look at this asteroid Cruithne,现在我们来看看 that has been referred to as Earth’s被称为第二个月球的 second moon, but that’s just a克鲁特尼小行星 sensationalist kind of thing. It is-但这种说法只是哗众取宠 what it is is an asteroid that’s in这只是一颗 orbital resonance with the Earth轨道与地球共振的小行星 which means- in this case it means that这说明 在这种情况下 its year is the same as Earth’s year;它的行星年与地球相同 but it’s not orbiting Earth, it’s also但它不围绕地球公转 orbiting the Sun but in a more kind of而是跟地球一样围绕太阳 elliptical orbit. So if we mistakenly而且轨道的形状更接近椭圆 thought it was orbiting orbiting the如果我们误以为它围绕地球公转 Earth then what would its orbit look会得出什么结论呢 like? It wouldn’t be a circle, it’d be那样它的轨道就不会是圆 some kind of而是某种 mix of circles and ellipses or something;圆形和椭圆的结合体 so let’s see.所以我们来看 So again we start out with the Sun at我们还是以太阳为中心 the centre;着手 Earth is orbiting and then this is Cruithne,地球在围绕太阳公转 this little asteroid that is orbiting克鲁特尼 with the same year.是与地球有着同样行星年的小行星 Now we’ve shifted to the perspective of现在我们将注意力转移到地球上 the Earth and the path that Cruithne is我们发现克鲁特尼运行的轨迹 tracing out is this kind of kidney bean绘制出来有点像芸豆的形状 shape – again this these aren’t the exact再强调一下哈 correct orbits but it’s roughly这些只是大致的运行模型 kind of like what’s going on. So we don’t并不是完全准确的轨迹 see an elliptical orbit; if we were wrong因此没有显示出椭圆状 and we thought Earth was the centre of如果我们错把地球 the solar system then Cruithne would当作太阳系的中心 be the sort of weird second moon tiny那克鲁特尼就会成为 asteroid guy that is orbiting us in this以芸豆的形状围绕我们远转的 kind of kidney bean shape. – (Brady: That would)像第二个月亮那样奇怪的小行星 (take some explaining if you believe that)-(布兰迪:“如果谁觉得地球是万物中心”) (the Earth was at the centre of)(“那解释起来确实需要费些口舌。”) (everything!) – Yeah that’s a kind of是的 complicated behaviour to explain,这解释起来确实很复杂 but I suppose it’s just built up of a但我推测这些轨道 circle and an ellipse kind of added是由圆形和椭圆叠加而成的 together, so maybe as soon as you saw也许你一看到它的样子 that you might invent that explanation.就可以描述清楚了 (You put these on Twitter but what have)(“在把这些发布到推特上之前”) (you done in the past?) – Yeah I used to run(“你都研究了些什么?”) this blog on Tumblr that- where I posted我之前在汤博乐上发布数学动图 mathematical GIFs and后来 back then I don’t think they were我觉得这些不如新的 quite as good as my new ones, I think I’ve我应该算是 sort of progressed a little bit. So有点进步吧 for example, you know, this was the new例如 这是新的克鲁特尼运动动画 Cruithne animation, this is the old one这是旧的 here. It’s explaining the same它们生成的形状相同 shape but it takes a little bit longer但是想要一探究竟 to see exactly what’s happening; possibly还需要花更多时间 because you don’t have that shift in可能是因为没有转换视角 perspective, you know where you establish我们先是以太阳为中心定点 the orbits with the Sun at the centre建立的轨迹 and then you shift to just following因为地球的位置固定不变 Earth because Earth is stationary.我们再将目光转移到地球 You can kind of see what’s going on, right?这样一切就清晰明朗了 对吧 (The Sun’s stationary too in that one)(“太阳在这里也是静止的诶”) Yeah the Sun is stationary as well. So if对 太阳也是静止的 we look at the new one, the Sun is also因此如果我们观察这颗新的克鲁特尼 still stationary right, but the fact that太阳仍然静止不动 the Sun is at the centre of the old one但其实太阳是旧克鲁特尼的中心 is maybe a bit confusing as well. Here这听起来好像也有点绕 I’ve just put Earth is the centre to我在这里把地球作为中心 emphasise that we’re doing a sort of以强调我们正在做一项 geocentric thing. In both I’ve done the地心模型研究 trick of having like stars in the在所有的模型中 background, which are just randomly我都用随机生成的点 generated points, but the stars that sort制成了星空背景 of swing around I think helps to show但是星星忽明忽暗 漂移不定 you’re in a sort of weird reference它们时刻提醒你处在一个 frame that’s rotating with the Earth.随着地球旋转的另类参照系里 (And then you’ve got another old one too from there?)(“所以旧的克鲁特尼也在里面吗?”) Yeah, related to this ratio of是的 这跟金星与地球的比例有关 Venus and the Earth: got this one here金星和地球身在其中 which is, you have Venus going around,金星和地球 you’ve got Earth going around, and you都在自转和公转 just draw a line between the two. It’s a只要将它俩画条线连起来就行了 bit different to tracing the relative这与追踪它们的相对路径有些不同 path but you get a similar shape, you get但可以得到一个类似的形状 that five-pointed shape that I pointed正是之前我们看到的五边形 out before. – (It’s fun stuff all this)(“行星真奇妙 对吧”) (planets isn’t it?) – Yeah, and I mean for me对 于我而言 it’s kind of just a way to talk about这只是其中一种 解释 the spirograph patterns, epicycloids,通过圆圈旋转得到的 that you get from circles rotating螺旋形图样和外摆线 的方式 around. It’s just kind of fun to plug举个例子 把金星和地球 in the numbers that roughly correspond大概对应的数字代入其中 to like Venus and Earth for example. And,会很有意思 of course, it’s not exactly 8 to 13 ratio当然啦 这个8比13的比例并不精确 but it gives the 5 pointed symmetry但由8+5=13 because 8 plus 5 is 13.可以推知五点对称 Today’s episode has been brought to you本集精彩由机智网提供 by Brilliant. Now we often focus on all我们最近经常关注他们的这些 their great math courses, like these ones,高质量数学课 诸如此类 but it seems appropriate today to let然而这是一个合适的时机 you know they happen to have this epic向大家介绍它们即将推出的 course on Gravitational Physics. As you这部史诗级的引力物理学课程 can see it’s jam如你所见 packed with stuff relating to today’s这里遍布了 video,与这期视频有关的内容 but going much much deeper of course.当然 深度要远大于此 Brilliant is fun, it’s engaging; it’s机智网不仅引人入胜 educational of course, but most寓教于乐 更重要的是 importantly it’s really interactive. Why它的最大亮点——互动性 not visit today and see what a great不如立即行动 resource they’ve created?去看看他们创造的绝妙资源宝库吧 Maybe sign up if it’s for you; or give a自用请注册登录 subscription as a gift to that person点击订阅作为礼物 who already has everything.送给那个无所不有的人 There’s 20% off a premium subscription by点击屏幕上的链接进入网站 going to Brilliant.org/Numberphile,订阅此频道 the address on the screen.可以享受八折优惠 Thanks Brilliant for supporting today’s episode.感谢机智网对本集的赞助
  • 2021-10-17超疏水材料为何能防水?2 buckets full of colored water?两满桶颜料水? Check.已确认 2 willing subjects?两名测试者? Check.已确认 A slow mo camera?一台慢速相机? Uh, check.嗯 已确认 Alright.好了 Let’s do this.我们开始吧 But wait… why is only one of them getting soaked?等等……为什么只有一个人湿透了? The chemistry behind this is pretty darn cool.这背后的化学反应相当酷 So cool in fact that we got the 2016 Chemistry Champions winner,这实在太酷了 让2016年化学冠军 Dr. Mallory Hinks, to help us out in this video.玛罗琳·辛克斯博士在视频里帮我们解惑 Raincoats, car windshields, waterproof phones.雨衣 汽车挡风玻璃 防水电话 They all use a little chemistry to stay dry.它们都用了一些化学物质来防水 To show how this works,为了展示它是如何工作的 we sprayed a Reactions team member with an industrial strength waterproof spray,我们对一名测试者喷洒一种工业强度防水剂 or what’s called a superhydrophobic coating.或者称之为超级疏水涂层 “Hydrophobic”meaning water-fearing or water-hating“疏水”意思是怕水或讨厌水 and”super”meaning ”a whole lot”“超级”的意思则是非常 Ah, quick safety note guys: spray the shirt.哦 安全小贴示:喷在衬衫上 Not yourself.不是喷你自己身上 So what IS happening?那发生了什么? Well, it turns out, this spray works by borrowing a waterproof tip from nature.嗯 事实证明这种防水剂借用了大自然的防水技巧 Check out this leaf hopper’s wing.来看一看这片叶蝉翅膀 Or this lotus leaf.或者这片荷叶 These surfaces repel water so well that a drop is just going这些表面防水效果很好 一滴水落在上面 to sit on top of them as a ball that’s pretty close to a spherical shape.会形成一个十分接近球形的球 See, if water drops on a flat surface like a table,看 如果水滴在像桌子这样的平面上 it flattens out into a mini puddle.它就会摊开形成一个小水坑 Scientists refer to a so-called “contact angle”.科学家们称之为所谓的“接触角” This angle is usually somewhere between zero and 120 degrees.这个角通常在大约0到120度之间 By comparison, water droplets on the lotus leaf have a contact angle of more than 150 degrees.相比之下 荷叶上的水滴接触角大于150度 And the water droplet on the leafhopper’s wing has a contact angle of around 170 degrees.而叶蝉翅膀的水滴接触角则约为170度 Getting as close to 180 as gravity will let you当接触角在重力允许范围内接近180度时 would give you an almost perfect sphere,水滴就会形成一个近乎完美的球形 meaning the surface doesn’t even get wet when a bead of water touches it.这意味着当一滴水接触物体时 其表面甚至不会变湿 So chemists have been trying to figure out所以化学家们一直想弄明白 how the lotus leaf and leafhopper’s wings do it.荷叶与叶蝉翅膀是如何做到这一点的 And they’ve made a lot of progress in trying to get those super hydrophobic他们在试图获得大于150度接触角的 for the contact angles of over 150 degrees.超疏水材料中有了重大进展 There are sprays that can waterproof shoes which are commercially available in some places,这是在有些地方能买到的给鞋防水的喷剂 and ones that can prevent your white shirt from getting stained from red wine.它还可以防止你的白衬衫被红酒弄脏 There’s even stencil street art in Seattle that only appears when it rains.在西雅图甚至有仅在下雨天出现的街头蜡纸艺术 Or should we say, only doesn’t appear when it suns?或者说 只是不会在晴天的时候出现? I don’t know.我不知道 To see some superhydrophobicity in action, we fired up the slow mo camera为了观察超疏水材料的作用 我们启用了慢速摄像机 and dumped water on superhydrophobic magic sand.先把水倒在超疏水魔力沙上 Here it is at 1000 frames per second.现在是每秒1000帧 But really, what I know you’ve all been waiting for但说真的 我知道你们等的是什么 — the chemistry of how this works.——这其中的化学反应原理 It all comes down to interactions we call surface chemistry这都归结为我们所说的“表面化学相互作用” and the shape of the surface at a very small scale.和其表面极其微小的结构 Most of the legwork is done by the surface大部分化学反应都发生在 — essentially at the itsy bitsy nanoscale all the way up to the microscale,——从纳米级到微米级来看 the surface is NOT flat.这个表面并不平整 It’s actually very bumpy and rough.它其实非常崎岖粗糙 These rough bumps are covered in a hydrophobic layer that has no time for water to join in这些粗糙凸起被疏水层所覆盖 水无法及时渗入 — sort of how water and oil never seem to get along.——这就好像水和油也从来不会相溶 So essentially the water is sitting atop a very oily,waxy bed of nails,水滴躺在一个油性的光滑钉子底座上 and it’s pushed upwards, away from the surface where it sits like a ball.它被向上推 离开水滴像球一样呆着的表面上 Because it’s on top of the surface, it can easily just roll away.由于它在表面顶部 很容易滑下去 This is great for lots of products, like rain jackets that use water repelling Gore-tex,这对很多产品都很棒 像使用了防水材料Gore-tox的雨衣 which is made from Teflon, or as we like to call it polytetrafluoroethylene.它由特氟龙制成 即我们一般说的聚四氟乙烯 Car windshields and windows are coated with polysiloxanes to the same effect挡风玻璃和车窗涂有相同效果的聚硅氧烷 –rain just rolls off instead of blurring your view.——雨水会滑下去而不是模糊你的视野 One of the most innovative uses may be coming to San Francisco soon.一个很棒的创意将很快在旧金山得到应用 The city is testing a paint to deter public urination.他们在测试一种防止人们随地小便的油漆 The hydrophobic paint would create a rough texture …这种疏水油漆会产生粗糙的纹理 so that anyone who tries to go wee on a wall,所以任何试图向在墙上小便的人 would, in fact, end up wetting themselves.最终反而会把自己弄湿 Thanks for watching us splash water around in the name of science.感谢观看我们以科学为名的泼水节目 For more, check out this great graphic from our friends at C&EN想要了解更多 请在简介里查看我们朋友在《C&EN》 and Compound Interest in the description below.和《化合物乐趣》中的美图 Thanks to Seattle Rainworks, Ultra-Ever Dry, and Dr. Mallory Hinks.感谢西雅图雨衣工厂和玛罗琳·辛克斯博士 Do you have any experiments you want us to try?你有什么想让我们做的实验吗? Leave them in the comments,and Hey!在评论中留言吧 就这样! Thanks for watching.感谢观看
  • 2021-10-17为什么这个天文台会向卫星发射激光If you want to know where you are, you can check on your phone.如果你想知道你的定位 你可以在手机上查看 It listens for signals from whole constellations of satellites in orbit,它能接收到来自整个在轨卫星系统的信号 and by triangulating all those signals and using a lot of maths,通过对这些信号进行三角测量及大量数学运算 it works out where you are and shows you a little dot on a map.就能获取你的定位 将其显示为地图上的一个小点 But how do the satellites know where they are?但这些卫星怎么知道自己在哪呢? There aren’t any landmarks in orbit for them to refer to.它们的轨道上没有任何可供参考的坐标 If satellites are in a high enough orbit, well away from the atmosphere,如果卫星所在的轨道足够高 距大气层足够远 then they can predict their position.它们就能推测自己的位置 They’ll just keep orbiting in about the same path:它们运行的轨道基本不变: there’s no atmosphere to slow them down.没有大气层削减它们的速度 But that’s not precise enough.但这样得出的结果不够精确 There will be distortions caused by gravity from the sun and moon,太阳和月球的重力 甚至是地球上的山脉 or even from mountain ranges down on Earth.都会导致偏差 So maybe they could use the other satellite signals, like GPS.或许它们也可以利用其他卫星信号 例如GPS But if they’re all relying on each other, that could steadily drift apart from reality.但如果卫星全都相互依赖 结果就会慢慢失真 Maybe they could track the stars or the features down on Earth,或许它们可以追踪恒星或地球上的标志物 but that’s not precise enough either.但这样结果也不够精准 At some point, something down here on Earth has to look up in the sky因此 地球需要从特定点将某种东西射向天空 and work out the position precisely.并计算出卫星的具体位置 And one of those somethings is hidden away in the countryside of southern England.其中一个设备就藏在英格兰南部的乡村里 It looks like a regular observatory, but it’s not looking at the stars.它看起来与普通天文台相似 却并不用来观星 – We track manmade satellites in various orbits doing various jobs.我们追踪处于不同轨道 具有不同功能的人造卫星 They all have to have special reflectors that enables the light to be returned to us.它们都需要有特制的反光板将光线反射给我们 And so we can measure the time of flight, and from the time of flight, derive the distance.这样我们就能测量光的飞行时间并用其测算距离 You send out a very short pulse of laser light.只需发射一束脉冲非常短的激光 You do that a thousand times a second.并且每秒钟发射一千次 Each of those shots, because you’re using such a tiny short-pulsed laser,由于所使用的是脉冲极短的激光 is 10 picoseconds long, which is about 3mm.每次发射只需10皮秒 约等于3毫米长的光波 That’s the limitation on your precision. So each shot is about 3-4mm precision.这就限制了精准度 所以每次发射都有3至4毫米的误差 – This station works around the clock, whenever the sky is clear.只要天气晴朗 该站全天工作 That’s why I’m here today:所以今天我来到了这里 there will be some genuine observations when the clouds break,当云散开后 我们将能观察到真实状况 but right now, I’m not actually disrupting anything.但现在我啥也看不清 But it does look significantly better after dark.不过天黑后 就好观察多了 – Because it’s a laser, it’s a very specific wavelength.因为我们用的是激光 有特定的波长 So you can filter, and that’s what lets you work in day and night.所以你可以对其进行筛选并实现全天工作 The main problem with the atmosphere is: the speed of light in a vacuum is a very well known constant.大气层带来的主要问题在于 众所周知 光在真空中的速度为常数 The speed of light through the atmosphere is variable而光在大气层中的速度是不定的 according to the mainly the pressure, but also temperature and humidity.其主要取决于气压 也取决于温度和湿度 So we measure those things on site, as well.所以我站也会测量这些数据 There’s probably about 35 active stations scattered around the globe,地球上分布着大约35个正在工作的站点 located predominantly in the northern hemisphere, which is a slight problem from a science point of view.主要分布在北半球 而这可能不太符合科学的观念 You’d like them evenly distributed all around the globe.它们本该均匀分布在世界各地 There’s a couple in Australia which are really important澳大利亚有一些站点 起到很大作用 because they’re providing a bulk of the data from southern hemisphere.因为它们提供了大量来自南半球的数据 Ideally, we’d have a more even distribution.理想状态下 站点分布应更加均匀 – Of course, as the light fades, there’s one assumption that we’ve been working on throughout this video:当然 随着光的衰减 在整个视频中我们一直在假设 that the earth, the ground we’re standing on, doesn’t move.地球 也就是我们脚下的这片土地 是静止的 And that’s not strictly true.但这严格来说并不属实 – In the early days of laser ranging, in the 60s,在激光测距刚刚出现的六十年代 it was the primary method by which they were deriving those early measurements of the drift between us and North America.这是测量我们和北美之间的漂移的主要方法 So you can see long-term trends,你可以发现一种大趋势 like the ice caps melting and the redistribution of mass from the ice caps to the equator.比如冰盖的融化 质量从极地冰盖到赤道的重新分布 All the data goes off to international databases, from all the sites all around the world.这些来自全球站点的数据都将进入国际数据库 Anyone, any researcher, anywhere can go and grab the international data set,各地的研究人员都能获得这些国际数据集 the data from us, from Australia, from North America, from China, from Russia,包括来自英国 澳大利亚 北美 中国 和俄国的数据 and can use that data to derive the orbits and do the research they need to do.然后用这些数据来计算轨道以及做研究 – Thanks very much to all the team at the Space Geodesy Facility.非常感谢空间大地测量站的所有团队 You can find out more about them and their work at the link in the description.请点击视频介绍中的链接以获取更多有关他们及其工作内容的信息
  • 2021-10-17如果遇到狼会发生什么?While working as an ODFW summer intern,在ODFW暑期实习期间 I had an exciting encounter with a wolf.遇到了一头狼让我兴奋不已 I was alone serving in an area for science of wolf activity我孤身前往 狼群活动研究区域 when I saw a wolf walk out of the forest.发现有头狼走出森林 As the wolf moved in my direction, it was clear that it didn’t know that I was there.它朝我走来 很明显并没有看到我 As it got closer, I said something quietly to alert the wolf.更靠近时 我悄悄发出声音使其警觉 As soon as I did, the wolf stopped in its track, trying to figure out what made the noise.之后 狼停下了脚步 想辨别是什么声响 It turned and ran as soon as it realized I was there.见到我之后 转头就跑 Running away is a wolf’s typical reaction to encountering a human.当狼遇到人时 典型行为就是跑开 There are a few other behaviors I could’ve seen during the same encounter.狼遇到人时也可能会有其他行为 Sometimes wolves will bark out when they feel nervous or threatened.有时 狼在感到不安或受到威胁时 会发出叫声 They might also follow a person at a distance它们也可能会保持一定距离尾随人类 until they are out of the area that the wolves feel protective of, like a den or feeding site.直到走出栖息地或取食地之类的安全区才停下 These bolder behaviors become more likely if there is a dog present,如果有狗闯入 狼群有可能会做出更大胆的行动 since wolves see dogs as intruders in their territory.因为狼群视狗为领地的侵略者 I can understand how someone might have felt threatened by this wolf.我可以理解被狼吓到的人 It’s hard to imagine that a wolf could be so close without noticing me,很难想象 狼离我那么近却没看到我 since they have excellent senses of smell and sight.因为它们嗅觉和视觉都很灵敏 But the breeze was blowing towards me carrying my sight away from the wolf.一阵微风吹来 我消失在狼的视线里 I was standing still with the trees behind me and a small tree in front of me.我身后是树林 前面是棵小树 我静静站在中间 And I was wearing green and brown clothing.那时我穿着绿棕相间的衣服 So make sense that the wolf didn’t notice me at first.所以它一开始没注意到我 就说得通了 If you encounter a wolf and it doesn’t run away at first,如果你遇到一只狼 它一开始并没有跑开 it may be because the wolf doesn’t know that you are there.可能因为它没注意到 A shout and an arm wave can let the wolf know.大叫或挥手臂 就能把它吓跑 Be ready to encounter all kinds of wildlife on Oregon’s wild lands.准备好 与俄勒冈州的野生动物们见面吧
  • 2021-10-17最大的教育误区This video is about learning styles.这期视频是关于学习风格的 What kind of learner are you?你是哪种风格的学习者? -I’m a visual person, so I have to see things, yeah. – Oh yeah, same.– 我是个偏视觉的人 我必须看到图像 – 对 我也一样 – I think visual learner. -Visual.– 我应该是视觉学习者 – 视觉 I mean, like, I remember formulas like auditory.我记公式是靠听的 I need to be like, interacting with the material.我需要动手操作 I like to learn by doing it myself.我喜欢在做中学 Very hands-on.必须动手 Hands-on learner.动手型学习者 Hands-on?动手型? So like, if I have a model, I’d like to look at that and look it over.如果有个模型 我喜欢拿过来反复看 Part of this video was sponsored by Google Search.本期部分视频由谷歌搜索赞助 There is this idea in education that教育界有一个观念 everyone has their own preferred way of learning,每个人都有自己偏好的学习方式 their so-called learning style.即所谓的“学习风格” If information is presented in accordance with the learning style,如果信息呈现方式与本人学习风格一致 well, then they’ll learn better.他们会学得更好 Now, there are dozens of different learning style theories,如今 有数十种不同的学习风格理论 but the most common one identifies four main learning styles,但最常见的理论把学习风格分为4类 visual, auditory, reading-writing, and kinesthetic or VARK for short.视觉 听觉 读写 动觉 即VARK分类法 Visual learners learn best from images, demonstrations, and pictures.视觉学习者通过形象 演示和图片学得最好 People may say things, but I can’t really take it in.可能会有讲解 但我总是听不进去 I just gotta see ’em act it out or write it or something.我得看他们演示 或者写下来什么的 Auditory learners learn best from listening to an explanation.听觉学习者通过听讲解学得最好 Like in school, I was always engaged in the lecture比如在学校时 我经常听讲座 and that was usually good enough to pass a test.这样通常就足以通过测试了 Reading-writing learners learn best from reading and writing.读写型学习者通过读和写学得最好 Like I can get pretty much anything out of reading a textbook or something.我通过读课本什么的就能学的挺好 And kinesthetic learners learn best by doing,动手型学习者最好实际操作一下 physically interacting with the world.即亲身与世界互动 Hands-on. You have to touch things,要动手 要摸得到实物 you have to play with things, you know, it’s a contact sport.能上手操作 这是接触性运动 You have to do it yourself.你要亲身实践 I want to try something with you, a little experiment.我想请你做个小实验 I want to show you 10 pictures of things我会向你展示10张图片 and I don’t want you to say anything while you’re looking at them,你在看的过程中不要说话 and at the end of the 10 you tell me how many you can remember.看完后 告诉我你能记住几个 – Okay. – Okay? – Okay. – Okay.– 好的 – 好吗? – 好的 – 好的 Now, learning styles make intuitive sense从直觉上看 学习风格是有道理的 because we know everyone is different.因为我们知道 人人都是不同的 Some people have better spacial reasoning.有些人空间推理能力比较好 Others have better listening comprehension.另一些人听力理解比较好 We know some people are better readers我们知道有些人善于阅读 while others are good with their hands.而另一些人善于动手 It’s sort of very much fits with a broad strain of thought这与最近西方传统中的一系列理念 in the recent Western tradition is,是相契合的 也就是 we’re all unique, we’re all different.我们都是独特的 各不相同 And so you don’t want to say, like, everybody learns the same way.没人想说 每个人学习方式都一样 That sort of conflicts with our feelings about what it means to be human.这与人类认为自己有独特意义的感觉相冲突 So doesn’t it make sense that people should learn better那么 用自己偏爱的方式学习效果更好 in their own preferred learning style?这种说法有道理吗? Well, teachers certainly seem to think so.当然 老师们似乎是这样想的 A survey of nearly 400 teachers一项对来自英国和荷兰的 from the UK and the Netherlands found that近400名老师的调查表明 over 90% believed that individuals learn better超过90%的老师相信 当学生们 when they receive information in their preferred learning style.以喜欢的学习风格接受信息时学得更好 Just like every professor has a different style of teaching,正如每个教授都有不同的教学风格 you have a different style of learning.你也有不同的学习风格 But when his teacher starts using visuals,当老师用视觉材料上课时 Johnathan finds it easier to focus若乔纳森感觉更容易集中注意力 and understand the material更能理解学习材料 so he might be a visual learner.那他可能就是视觉学习者 Can you tell me what that means to you?能告诉我您的看法吗? Like, what does it mean to be a visual learner?比如 视觉学习者是什么样的? To me it means that for me to learn something对我来说 要学什么东西 sometimes you need to draw it or I need to write it down有时需要画下来或写下来 or I need to see a picture or a movie.或者要看到图片或视频 For example, science classes, I get bored easily just listening比如上科学课 光听讲我很容易无聊 and I think it’s more interesting for me to actually be able to do it.我感觉能实际操作要更有趣一些 How do you know that you’re a visual learner?你是怎么知道自己是视觉学习者的? I don’t, I just assumed.不知道 我猜的 To take advantage of learning styles要利用学习风格理论教学 then teachers need to do two things.老师们需要做两件事 First, identify the learning style of each of their students.首先 要识别出每个学生的学习风格 And second, teach each student in accordance with their learning style.然后 按学生各自的学习风格分类教学 On the VARK website it says, once you know about VARK,VARK的网页上写着 一旦你懂VARK its power to explain things will be a revelation.它强大的解释力会让你豁然开朗 But before you take an online learning styles quiz,但在你做在线学习风格测试之前 it’s a good idea to ask, do learning styles even exist?最好先问一下 学习风格真的存在吗? I mean, do you have one?你真的有学习风格吗? And if you’re taught in accordance with it,如果按你的学习风格教你 would you learn better?你会学得更好吗? Well, you could test this by running a randomized control trial你可以通过随机对照实验测试一下 where first you would identify learners首先要识别学习者 with at least two different learning styles,分为至少两个学习风格类型 say visual and auditory比如视觉和听觉 and then randomly assign learners to one of two educational presentations,然后随机指定学习者到两个教学演示课里 one visual, one auditory.一个视觉的 一个听觉的 So for half of the students这样对一半学生来说 the experience will match their learning style听课体验与他们的学习风格相符 and for the other half it won’t.而另一半则不符 And then you give everyone the same test.然后给所有人相同的测试 If the learning style hypothesis is correct,如果学习风格的假设成立 the results should show better performance那么测试的成绩应该是 when the presentation matches the learning style课程演示与学习风格相符的学生 than when they’re mismatched.高于不相符的学生 I tried a very unscientific version of this experiment on the street.我在大街上做了个不太严谨的类似测试 For some people, I matched their learning style对一些人 我的测试与他们学习风格相符 so I showed visual learners pictures of 10 items,向这些视觉学习者展示10个物品的简图 but for other visual learners I read out the items instead.但对其他视觉学习者 只念物品的名称 – Bell, penguin, sun. – Okay, I’m maxed out.– 钟 企鹅 太阳 – 好了 我记不住了 – How many can you remember? – I don’t know.– 你能记住几个? – 我不知道 Hair, knife, duck, heart, butterfly.头发 匕首 鸭子 心型 蝴蝶 Apple, bicycle, guitar.苹果 自行车 吉他 There was a spider. Did I say eye already?有蜘蛛 眼睛我说过没有? – Trumpet, pear. – Pear.– 喇叭 梨 – 梨 – Butterfly. – Duck. – Knife.– 蝴蝶 – 鸭子 – 匕首 – Knife. – Boat.– 匕首 – 小船 – Heart. – Knife. – Heart.– 心型 – 匕首 -心型 I couldn’t tell you the rest, that’s all I got.其余说不出来了 我只记得这几个 Most people could remember only about five or six things.大部分人只能记住5到6个图片上的物品 – Yeah, yeah. All right. – Six, six is not bad.– 对 对 好吧 – 6个 很不错了 – Six. – Six out of 10– 6个 – 10个记住6个 – which is not bad, right? – Oh, all right, yeah.– 很不错了 对吧? – 嗯 好吧 对 That’s a passing score.已经及格了 – Oh. – Candle. – Everyone forgets the candle.– 哦 – 蜡烛 – 都把蜡烛忘了 But a few could remember substantially more,但有些人能记住的更多 say, eight or nine items.比如 能到8到9个 Bug, I don’t know if I said bug.虫子 不知道说过虫子没有 Guitar, bike, eye, bell, spoon, sun, chair.吉他 自行车 眼睛 钟 汤匙 太阳 椅子 I’m forgetting the last two.最后两个忘了 – That’s pretty good. Oh, cool. – Eight is really good.– 那很不错了 很棒 – 8个很好了 – Nine? – Nine out of 10.– 9个? – 10个记住9个 Nine, very impressive.9个 太厉害了 But the reason didn’t seem to be because但成绩好似乎不是因为 the presentation matched their preferred learning style测试方式与他们偏好的学习风格相符 but because they employed a memory strategy.而是因为他们用了记忆技巧 So as you were showing I was making an order in my head.在你展示时 我会在心中排序 So as I saw more I would just add it to the list这样看到新的 我就加进原来的列表里 and I was repeating the list as I was looking at them并且边看边重复这个列表 so I could just say it out loud.这样就能把它大声念出来 -Did you try a strategy while you were looking at those pictures? – Yeah, yeah.– 你看图片时有用记忆技巧吗? – 对 是的 So I guess I tried creating a story我试着把它们编成故事 ’cause it’s easier to remember a story than just individual objects.因为记故事比记每个物品要容易 So I tried to tie it all into one story.所以我试着把它们编进一个故事 This is all obviously anecdotal evidence,这些证据显然都不太严谨 but rigorous studies like the one但类似我这种粗略测试的 I outlined have been conducted.严谨研究也有人做过 For example, one looked at visualizers versus verbalizers比如一项研究是关于“视觉型者与言语型者” instead of visual versus auditory learners.而非我做的“视觉与听觉学习者” The study was computer-based,研究是基于计算机的 so first students’ learning styles were assessed首先 评估学生们的学习风格 using questions like, would you rather read a paragraph用的问题如 “描述原子的一段文字或示意图 or see a diagram describing an atom?你更愿意看哪个?” The researchers also provided some challenging explanations研究者也提供了一些挑战性的解释 with two buttons, visual help or verbal help.设了两个按钮 “视觉帮助”或是“文字帮助” The visual one played a short animation视觉帮助会播放一个动画短片 whereas the verbal help gave a written explanation.而文字帮助会给一段文字解释 From these measures combined, the researchers categorized通过所有这些方法 研究者把学生们 the students as either visualizers or verbalizers归类为视觉型者和言语型者 and then the students were randomly assigned然后学生们被随机指定到两个班 to go through a text-based or picture-based 分别基于文字和图片 lesson on electronics.上电子学课程 When a student hovered their mouse over key words在上文字课的组里 当学生把鼠标 in the lesson in the text-based group,放在一些关键词上时 a definition and clarification came up.屏幕会弹出文字解释和说明 But in the picture group,但在上图片课的组 an annotated diagram was shown instead.却会弹出注释性图表 And after the lesson, the students did a test to assess their learning.课后 学生参加了测试以评估学习效果 The students whose preferred learning style matched their instruction上课方式与他们学习风格相符的学生 performed no better on the tests than those whose instruction was mismatched.并不比不相符的学生表现得更好 The researchers ran the test again研究者用61个没上过大学的成年人 with 61 non-college-educated adults重做了该实验 and found exactly the same result.结果完全一样 But learning styles are a preference但学习风格是一种偏好 so how strongly do learners stick to their preference?那么学习者有多依赖于这种偏好呢? Well, in a 2018 study during the first week of semester,在2018年的一项研究中 学期第一周 over 400 students at a university in Indiana印第安纳州一所大学的400多名学生 completed the VARK questionnaire参加了VARK问卷调查 and they were classified according to their learning style.他们按学习风格被分为4组 Then at the end of the semester然后 学期结束时 the same students completed a study strategy questionnaire.这些学生完成了学习策略问卷 So how did they actually study during the term?那么这期间他们实际的学习方式是什么呢? Well, an overwhelming majority of students used study strategies绝大多数的学生所用的学习策略 which were supposedly incompatible with their learning style.都与他们本来的学习风格不一致 And the minority of students who did而少数学习策略与学习风格相符的学生 did not perform significantly differently on the assessments in the course.测验表现与其他同学也没有太大不同 The visual auditory reading-writing, kinesthetic视觉 听觉 读写 动觉 or VARK model came about from Neil Fleming,也叫VARK模式 提出者尼尔·弗莱明 a school inspector in New Zealand.是新西兰的一名学校督查员 Describing the origins of VARK he says,他在解释VARK模式的起源时说 I was puzzled when I observed excellent teachers当我观察到一些优秀老师教不好某些差生 who did not reach some learners and poor teachers who did.而差的老师却可以时 我很困惑 I decided to try to solve this puzzle.我决定要解开这个困惑 There are, of course, many reasons for what I observed.当然 我观察到了很多种原因 But one topic that seemed to hold some magic,但其中一种似乎有些”魔力” some explanatory power,有一点解释力的说法 was preferred modes of learning, modal preferences.是“偏好的学习模式” 模式偏好 And thus, VARK was born.这样VARK模式就诞生了 There was no study that revealed尚无研究表明 students naturally cluster into four distinct groups.学生按学习偏好天然可分为4个不同的组 Just some magic that might explain只是有一些”神秘力量”可以解释 why some teachers can reach students while others can’t.为什么有的老师教得好 有的教得不好 But how can this be?但怎么会这样呢? If we accept that some people are more skilled如果我们承认 有些人比其他人更善于 at interpreting and remembering certain kinds of stimuli理解和记忆某些种类的刺激 than others like visual or auditory,如视觉和听觉刺激 then why don’t we see differences in learning那为什么用不同的演示方式 我们看不到 or recall with different presentations?学习效果和记忆力的差异呢? Well, it’s because what we actually want people to recall那是因为 我们实际想让人们记住的 is not the precise nature of the images不是图片的准确细节 or the pitch or quality of the sound.或声音的高低和质量 It’s the meaning behind the presentations.而是演示背后所表达的意义 There are some tasks that obviously require the use of a particular modality.有些任务显然是要用特定的感觉模式的 Learning about music, for example, should have an auditory component.比如 学音乐的话 听的部分必不可少 Similarly, learning about geography will involve looking at maps.同样地 学地理必须要看地图 And some people will have greater aptitude而一些人学习某一技能时 会比其他技能 to learn one task over another.有更好的天赋 Someone with perfect pitch, for example,比如 有绝对音高的人 will be better able to recall certain tones in music.更容易记住音乐中某些旋律 Someone with excellent visual-spatial reasoning有出色的视觉空间推理能力的人 will be better at learning the locations of countries on a map.更善于学习地图上的国家位置 But the claim of learning style theories但是 学习风格理论断言 is that these preferences will be consistent across learning domains.这些风格偏好在各学习领域都适用 The person with perfect pitch有绝对音高的人 should learn everything better auditorily靠听觉学什么都会更好 but that is clearly not the case.但显然不是这样的 Most people will learn geography better with a map.大部分人用地图学地理的效果更好 Review articles of learning styles consistently conclude一些学习风格的评论文章的一致结论是 there is no credible evidence that learning styles exist.没有学习风格存在的可信证据 In a 2009 review, the researchers note,2009年一篇评论中 研究者指出 “The contrast between the enormous popularity of the learning styles approach一方面学习风格理论在教育界备受推崇 within education and the lack of credible evidence for its utility is,一方面又缺乏该理论的效用的可信证据 in our opinion, striking and disturbing.”这强烈的对比 让我们既震惊又不安 If classification of students’ learning styles has practical utility,即便对学生进行学习风格分类有实际效用 it remains to be demonstrated.那也还有待于证实 What we’re expecting is, if your style was honored我们的预期是 如果你的确有学习风格 you’re going to perform better than if你的表现应该会比 you had some experience that conflicted with your style.学习经历与自身风格冲突时的表现要更好 And this is where we don’t see any support就是在这一点上 我们看不到任何 for the learning styles theory.支持学习风格理论的证据 One of the reasons many people find learning styles so convincing许多人感觉学习风格有说服力的原因之一 is because they already believe it to be true.是他们已经先入为主地相信它存在了 For example, they might already think that they’re a visual learner,比如 他们可能已经认为自己是视觉学习者 and then when a teacher shows them a diagram of,这样 当老师向他们展示出一幅 say, a bike pump and suddenly the concept clicks,比如打气筒示意图时 他们突然灵机一动 well, they interpret this as evidence for their visual learning style.就把这理解成自己是视觉学习者的证据 You already believe that learning styles is right.你已经相信学习风格是存在的 When you have an experience the first thing you think is,当你也有类似体验时 最先想到的是 is that in some way consistent with learning styles?这是不是在某种程度上与学习风格相符? And if it is, you don’t think further.如果是 你就不再深入去想了 When in reality that diagram might just be而事实是 那个示意图可能只是 a great diagram that would have helped anyone learn.对任何人学习都有很好的帮助 When we already believe the world to be a certain way,当我们已经认为世界按某些方式运行 then we interpret new experiences to fit with those beliefs我们就会拿新的经历来套用这些观念 whether they actually do or not.而不管是不是适用 So if learning styles don’t improve learning,那么 如果学习风格理论不能帮助学习 then what does?什么能呢? Well, there’s a large body of literature that supports the claim that有大量文献都支持这样一种观点: everyone learns better with multimodal approaches用多模式的方法 人人都能学得更好 where words and pictures are presented together就是把文字和图片一起展示 rather than either words or pictures alone.而不只是单独展示文字或图片 Now there’s gonna be words as well as the picture.这次既有文字又有图片 We’re gonna see if this is any better.看看会不会好一些 This is known as the multimedia effect,这被称为“多媒体效果” and it explains in part, at least,这至少部分解释了 why videos can be such powerful tools for learning视频为什么是如此强大的学习工具 when the narration complements the visuals.因为解说是视觉图象的良好补充 – Duck. – Duck.– 鸭子 – 鸭子 – Heart. – Heart.– 心型 – 心型 In my PhD research, I found做博士研究时 我发现 explicit discussion of misconceptions was essential在做物理学导论的多媒体教学时 in multimedia teaching for introductory physics.对错误观念进行明确讨论是至关重要的 – How many is that? – Six.– 答对了几个! – 6个 Six, okay, that’s good.6个 还不错 That is a whole 50% better.整个提高了50% Do you think that was easier?你们觉得这样会更容易吗? – Yeah, yeah, 100%, 100%. – Yeah, with the words, yeah.– 对 绝对的 – 对 带文字更容易记 Ultimately, the most important thing for learning归根结底 对于学习最重要的 is not the way the information is presented不在于信息的呈现方式 but what is happening inside the learner’s head.而在于学习者如何在头脑中思考处理问题 People learn best when they’re actively thinking如果他们能积极地思考材料 解决问题 about the material, solving problems or imagining what happens或想象不同变量改变会如何影响结果 if different variables change.学习的效果才最好 I talked about how and why we learn best在我的一期视频《思考的科学》中 我谈过 in my video, “The Science of Thinking” so check that out.怎样学最好 为什么 大家可以找来看下 Now, the truth is, there are many evidence-based如今事实是 有很多被证明有效的 teaching methods that improve learning.教学方法可以帮助学习 Learning styles is just not one of them.而学习风格论并不在其中 And it is likely, given the prevalence of the learning styles misconception而且 鉴于学习风格论错误观念的泛滥 that it actually makes learning worse.这很可能会损害学习效果 I mean, learning styles give teachers unnecessary things to worry about,学习风格论让老师为一些没必要的事担心 and they make some students reluctant to engage with certain types of instruction.也让学生们不愿意接受某些方式的指导 And all the time and money spent on learning styles而且 所有花在学习风格及相关培训上的 and related training could be better spent on interventions时间和金钱 本该花在真正能提高学习 that actually improve learning.的辅导方法上 You are not a visual learner nor an auditory learner你不是视觉学习者 或听觉学习者 nor a kinesthetic learner, or more accurately,或动觉学习者 更确切地说 you are all these kinds of learner in one.你融汇了所有这些学习风格于一身 The best learning experiences are those that involve最好的学习体验应该包含 multiple different ways of understanding the same thing.理解同一事物的多种不同方式 And best of all, this strategy works not just for最好的是 这个策略不只对一类人有效 one subset of people but for everyone.而是对所有人都有效 [Radio tuner chirping][无线调频声音] This part of the video was sponsored by Google Search.这部分视频是由谷歌搜索赞助的 Now, there are lots of topics out there that are controversial如今 有争议的话题很多 like learning styles, for example.比如关于学习风格的讨论 Most people believe learning styles are a thing大部分人认为学习风格是存在的 whereas educational researchers而教育研究者们发现 find no robust evidence for them.没有其存在的有力证据 And if you search for learning styles,如果你在谷歌上搜索“学习风格” you’ll get lots of sites with resources and quizzes.你会看到很多相关的资源和评测网站 But if you search for learning styles debunked,但如果你搜索 “学习风格遭驳斥” well, then you’ll find articles about about也会找到很多文章告诉你 how there is very little evidence for the learning styles hypothesis.支持学习风格假说的证据是多么的少 I think one of the most common traps people fall into我认为人们容易掉入的最常见陷阱之一 is only searching for information that confirms what they already believe.是只搜索与他们已相信的理论相符的信息 A common mistake is putting the answer you’re looking for普遍的错误是 把你要找的答案 right in the search query.直接输入搜索框 A better idea is to try another search,更好的做法是 多搜索一次 adding debunked or false at the end and see what comes up.在搜索词后加上“驳斥”或“虚假”再看结果 And Google makes it easy to get more detail而且谷歌能让你很容易得到更多 about the source of the information.有关信息来源的细节 Just click the three dots next to any search result只需点击搜索结果页旁边的的三个点 and then you can judge for yourself你就能自己判断 whether the information is trustworthy该网页信息是否可信 and if you want to visit the site.并决定要不要访问 A Google Search is meant to surface谷歌搜索本意是要呈现 the most relevant information for your query.与你的查询最相关的信息 But it’s up to you to formulate that query,但怎样设置查询词取决于你 try a few different searches,尝试一些不同的搜索 and assess whether the information is reliable.评估搜索结果信息是否可靠 And the whole point of Veritasium is to get to the truth.《Ve元素》全部的意义在于探究真相 So I’m excited to encourage everyone所以 我特别鼓励大家 to think more critically about how we get information.要更批判性地思考我们获取信息的方式 I want to thank Google for sponsoring this part of the video感谢谷歌对这部分视频的赞助 and I want to thank you for watching.并感谢大家的收看
  • 2021-10-17从沙子到硅:微芯片的诞生The world is producing data at an unprecedented rate,这个世界正以前所未有的速度产生数据 faster than our ability to analyze and understand it.远远超越了我们分析和理解数据的能力 To move, store and compute all of these data对这些数据进行传输 存储和计算 requires incredible processing power.需要难以想象的处理能力 From the blazing speeds of our devices从设备的高速运算 to blazing trails within AI,到AI应用的极速发展 Intel builds chips that are in the heart of nearly everything.英特尔制造了几乎一切事物的核心–芯片 Within every Intel chip manufacturing facility across the globe,在全球每一家英特尔芯片制造工厂 innovators are pushing the limit of science,创新者们都在突破科学的极限 and literally rearranging atoms to create groundbreaking technology.真正以原子重新排序的方法创造突破性技术 This strong silicon foundation is what gives each Intel chip limitless potential.这种强大的硅基赋予了英特尔芯片无限潜力 At the heart of all modern electronics,在所有现代电子产品的核心部分 the transistor is a tiny switch,晶体管是一个微型开关 ten thousand times smaller than the human hair是人类发丝细微一万倍 that controls the flow of electrons through a circuit.它控制着电路中的电子流 To build the processer,要制造一个处理器 billions of transistors are packed to an area no larger than a fingernail.就需要将数十亿个晶体管封装在不超过一个指甲盖的面积内 It’s one of mankind’s most complex feats and remarkable achievement英特尔每一代新的处理器 that Intel has essentially doubled transistor density几乎都将晶体管的密度提高了一倍 in every new generation of processers.这是人类最复杂的壮举之一 也是一项了不起的成就 The process begins when silicon-rich sand is melted and cooled,在整个加工过程的开始 我们将富含硅的沙子熔化并冷却 forming a solid, which is then sliced into wafers.形成固体 然后将它切割成晶圆 Once inside an Intel fab未加工的晶圆进入英特尔工厂后 the raw wafers begin their long journey through an incredibly complex process.就开始了其漫长而复杂的加工旅程 They’re loaded in the front opening unified pods, or FOUPs,这些晶圆将被装载到前开式晶圆传送盒中 which travel hundreds of miles along Intel’s automated superhighway.并沿着数百英里的英特尔自动高速轨道传输 They’re linked from tool to tool,使用不同工具的加工后 晶圆被链接到一起 as processors are painstakingly built up on each wafer.在每个晶圆上都精密地构建了处理器 The wafer first goes through a series of important steps, such as photolithography,晶圆首先通过一系列重要步骤 例如光刻 ion implantation, and etching,离子注入和蚀刻 that prepare for the critical transistor formation process.为关键的晶体管形成过程做好准备 Intel was the first to manufacture three dimensional transistors called FinFETs,英特尔率先生产了名为Fin FETs三维晶体管 FinFET construction requires first building a channel in the form of a fin.要制造FinFET 首先要建造一个鳍状的通道 Intel has devised several innovations英特尔设计出多项创新技术 to overcome foundamental barriers to continue transistor scaling,来克服持续扩大集成电路规模的主要障碍 one such innovation is a breakthrough fabrication method called gate-last,其中一项创新是称为后栅极的突破性制造方法 it involves building, then removing a temporary gate,它采用先建造临时栅极 再将其移除的方法 in order to precisely place the dielectric material and metal gate.来精确放置介电材料和金属栅极 This allows for the gate to wrap around the fin这样能够让栅极包裹鳍状通道 and control the flow of electrons through the channel.同时得以控制通过通道的电子流 Another invention moves the transistor contact directly over the active gate.另一发明是将晶体管接触层直接移动到有源栅极上 To accomplish this, the gate material is recessed要实现这一点 需要使栅极材料凹陷 and then filled with insulating dielectric material再填入绝缘介电材料 to prevent the creation of the short circuit.以防止发生短路 Next, the dielectric near the gate is etched,接下来 对栅极附近的电介质进行蚀刻 filled with metal,填充金属 recessed and capped,凹陷加工并加顶 to allowing novel self-aligning process that enables the high density contact geometries.以实现高密度基础层几何结构的新型自对准工艺 Now, the dielectrics are etched selectively to expose only the desire part现在选择性地对介电材料进行蚀刻 that connected to the first metal lines.以暴露连接第一条金属线所需的这部分 This is done through an innovative via etch and deposition scheme,这是通过创新的通孔蚀刻和沉积方案完成的 allowing contact over active gate to happen.让有源栅极上的接触层得以成型 Finally, dozens of layers of metal interconnected lines are added to complete the circuit.最终 添加数十层金属互连线以完成电路 After more than a thousand of these complex steps,经过一千多道复杂的工序后 the wafers are finally prepared for singulation and packaging.最终就可以准备晶圆的切粒和封装了 Innovative processor packaging不断创新的处理器封装方式 has become a critical feature of advanced computing architecture,已经成为先进计算机架构的关键特性 2D and 3D packaging technologies are enabling new device’s form factors2D和3D封装技术可适配新设备的外形尺寸 and additional boosts in performance and energy efficiency.并进一步提升了性能和能效 Testing of the final product ensures that最终产品测试可确保每个芯片 every chip exceeds our performance and quality standards.都能超过我们的性能和质量标准 In addition to adding more performance and features with each new processor generation,除了为每一代新处理器增强性能和凸显特性外 Intel’s integrated design and manufacturing capabilities have enabled humanity英特尔的一体化设计和制造能力 to innovate game changing technologies推动了革命性的各种技术创新 that impact nearly every facet of modern life对现代生活的方方面面产生了深远的影响 Intel keeps powering the world,英特尔持续为全球科技提供动力 at the same time, we’re powered by you,与此同时 正是你们赋予了英特尔前进动力 the makers, the dreamers, the doers,你们是创造者 梦想者 实践者 the people who share in our history of making the world你们与英特尔一起见证着这个世界 smarter, faster and more connected变得更智能 更快捷 联系更紧密
  • 2021-10-17为什么赤道附近生活着更多物种?“This episode is supported by Prudential”本片由保诚保险公司赞助播出 Here in Tambopata Peru, EO Wilson once found more species of ant in a single tree than在秘鲁坦波帕塔 爱德华·威尔逊在一棵树上找到的蚂蚁种类 there are in all of the British Isles.比整个不列颠群岛的蚂蚁种类还要多 Scientists have seen this pattern all over the world.科学家在世界各处都发现过这种情况 More species exist near the tropics.在热带附近生活的物种比其他地方的多 Why is that?为什么会这样呢 In one night here in the Peruvian rainforest, I saw more insects in an hour在秘鲁雨林的一个晚上 我一小时内看到的昆虫数量 than I’ve seen in my entire life, total.比我一生中看到的昆虫加起来都要多 It’s not just insects.不只是昆虫 Birds, mammals, plants…鸟类 哺乳动物 植物等等 Regions like this, tropical rainforests are some of the most biodiverse places on Earth.热带雨林是世界上最具有生物多样性的地方之一 It’s not just the abundance of it,生物多样性不仅指生物数量丰富 it’s how many different species we find in a given area.也指我们在给定区域发现的生物种类的丰富度 But why is that?但是 为什么会出现这种情况呢? It might seem obvious, or even like a silly question, but the more you think about it,答案可能显而易见 这甚至是一个愚蠢的问题 但越深入思考 the weirder it gets, because life has shown it can succeed pretty much anywhere, from你会越觉得奇怪 因为从山巅到海底 the top of the highest mountains to the bottom of the ocean.生命已经证明它们几乎能存活在任何地方 Yet Earth’s most biodiverse places但地球上最具生物多样性的地方 are always regions like this, tropical rainforests.总是在像热带雨林这样的区域 One reason why is maps lie to us.一个原因是 地图欺骗了我们 Rectangular projections are distortions of a sphere that make the poles look bigger and球体投影成矩形时会产生形变 这一形变使得 tropics look smaller than they really are.两级看起来比实际情况更大 而热带地区看起来更小 When in reality, the tropics contain about 40% of area on Earth.而实际上 热带地区面积约占全球面积的40% Unsurprisingly, larger areas usually have more species.毫无疑问 更大的面积能容纳更多物种 In less than half a square kilometer in the Amazon, we can find as many tree species as在不到半平方公里的亚马逊森林里 我们能找到的树种和 we find in four million square kilometers of temperate forest.在400万平方公里温带森林里找到的物种一样多 Species here are at a higher density.热带地区的物种密度更高 There must be something special about tropical ecosystems.热带生态系统一定有特别之处 Climate is one factor.气候是一个因素 When we look at plant fossils and when and where we can find them通过观察植物化石 和它们在自然气候历史中被发现的时点 in this climate history, tropical forests are older than temperate forests,我们发现 热带雨林比温带森林历史悠久 they’ve had more time to get rich.它们有更多时间来变得富饶 But just because the tropics don’t have cold winters.然而 因为热带地区没有寒冬 then they survive at ice age doesn’t mean that’s easy to survive here而渡过冰期的生物未必在热带也易生存 There are dry and wet seasons, they have to competition for resources,热带有干燥和湿润的季节 有资源竞争 no matter what kind of organism you are, there’s a lot of stuff that wants to eat you.无论你是什么物种 这里都有许多其他生物想吃掉你 不行 走吧 On average the tropics are warm and they get plenty of water.总的来说 热带地区气候温暖 水量充足 This part of the planet gets more average solar radiation throughout the year.这里的植物年均日照量比其他地区更高 Which means that plants and the animals they support get more energy,这就意味着热带地区的动植物拥有更多的能量 they are more productive.更高产 But this still only explains why there’s *more* life,但这只能解释生物数量的丰富 not why so many *different* kinds of life.而不能解释物种的多样 If you have a pie, more people can get a slice相比于把一块馅饼切成几份 每份分给一个人 if you cut it up into a thousand tiny ones vs just a few.把馅饼切成几千份 就能分给更多的人 And in ecosystem we call these slices niches在生态系统中 我们称这些馅饼为微环境 It’s the conditions, the habitat that one organism needs to flourish,这是生物繁荣所需要的条件和栖息地 and here in the rainforest, there’s a lot of slices.在雨林中 有许多微环境 Organisms that live at higher latitudes have to be little more adaptable,生活在高纬度的生物 其适应能力必须强一些 be able to handle more different conditions.以便应对不同环境 One week it might be snowing.可能前一周还在下雪 The next, flowers and fish are everywhere.紧接着就花开鱼跃 Specialization is too risky, you’ve gotta be adaptable.只擅长在某种环境生存会太过危险 因此你要变得适应力强 Life is more stable in the tropics.热带地区的生物更稳定 One thing I noticed here in Peru is the sun sets a lot earlier here this time of year我注意到 在秘鲁 每年这个时候的日落时间 than what I’m used to back at home.比我家乡的日落时间要早得多 Here near the equator there’s essentially the same number of hours在赤道附近 无论在哪个月 in day and night no matter what month it is.白天和黑夜的时间都几乎相同 Let’s say you’re a bird that eats insects, and maybe these bats over here假如你是吃昆虫为生的鸟 或者以那里的蝙蝠为食 You’ve got the same number of hours to do your feeding.你们捕食的时间是相同的 The birds get the day shift, the bats get the night shift.鸟类白天捕食 蝙蝠晚上捕食 You get to split that niche evenly.你们平分了这个微环境 That wouldn’t work at higher latitudes and more temperate climates.这一现象在高纬度和温和气候下不会发生 There’s simply just too much change, too much disruption for these species to keep track of.因为会有很多变数 很多因素会干扰这些生物规律 And this might explain a reason why more species coexist near the equator.这可能是生物更多在赤道附近共存的原因 The tropics are crowded, so the competition for resources is extreme.热带地区很拥挤 因此对资源的竞争很激烈 That competition drives organisms to specialize, like how we see ants or caterpillars that竞争迫使生物变得善于在某种特定环境生存 就像我们所看到的一些蚂蚁或毛毛虫 might be able to live on just one single type of plant.它们可能只能生活在一种植物上 But because climate and seasons are more stable, that specialization isn’t as risky.但由于气候和季节较稳定 专精于某一环境并不危险 More species, less area.更多的物种 更小的区域 These theories are really good at explaining这些理论很好地解释了 why there’s so many species in the tropics NOW, we’re still missing the beginning为什么热带有这么多物种 但我们还没解释一开始的问题 where those species came from.即这些物种从哪里来 It’s possible that evolution is actually working on overdrive here near the equator, speciation,在赤道附近 进化很可能加速进行 the creation of new species by various natural forces,需要多种因素共同促成的新物种 actually happens FASTER near the equator.在赤道附近能更快出现 Each generation of living things gathers changes, mutations, some are good,每一代生物都在积累变化 突变 其中一些是好的 some are bad, some are neither, but it isn’t until those changes are passed on to the next generation一些是坏的 一些直到传给下一代才会显现 that natural selection and time can do their thing .自然选择和时间会让一切发生 The reason that bacteria are so good at adapting is because they reproduce quickly,细菌之所以适应力强 是因为它们繁殖的很快 they have more generations in less time.在更短的时间内 它们能制造出更多后代 The same thing happens here in the rainforest. Plants and animals同样的事在雨林里重复上演 grow up faster, they can have more generations.植物和动物长得越快 它们就能繁育越多后代 This drives competition, this is what forces plants and animals to specialize这就导致了竞争 迫使动植物像我们之前看到的一样 in all of the amazing ways that we’ve seen.擅长以一些惊人的方式生存 This theory, that evolution happens faster near the equator, finally ties together the赤道附近的生物进化更快这一理论 ideas of time, area, and energy to explain the origin of biodiversity.将时间 面积 能量的概念联系在一起来解释生物多样性的起源 There’s an idea that says the tropics are so well suited to the creation of new species…一个观点是 热带地区适合新物种产生 that it’s like an engine for biodiversity它就像产生新物种的引擎 Another idea says the tropics are so rich and productive, and the climate’s so stable,另一个观点是 热带地区肥沃富饶 气候稳定 that species don’t go extinct as fast.因此这里的生物不会灭亡太快 More species are born here and species live longer here在热带地区 生物繁衍更多 生存时间更长 The tropics are like a cradle AND a museum.这里既像一个摇篮又像一个博物馆 Scientists even think that over many many years, species from places like this科学家甚至认为 多年后 这些地方的物种会 go and seed biodiversity throughout the rest of the world.遍布世界其他地方 形成生物多样性 This is why it’s so important to protect the rainforest这就是保护雨林的重要性 to preserve life’s cradle and museum.保护雨林就是保护生命的摇篮和博物馆 To keep it from being cut up,让它们免遭砍伐砍伐 because more area means more species.因为更大的面积意味着更多的物种 To keep the climate from changing, to keep this place stable and rich.保持气候稳定 保持该区域稳定富饶 Chemists know all the elements on the periodic table化学家了解元素周期表里所有的元素 Physicists probably know all the subatomic particles that make up matter.物理学家可能了解所有构成物质的亚原子粒子 But biology still hasn’t answered one of its most basic questions:但生物学里 一个最基本的问题还没有答案 how much life IS there?那就是 这里有多少生物? EO Wilson once wrote that “unlike the rest of science,爱德华·威尔逊写道 “和其他科学不同 the study of biodiversity has a time limit”.生物多样性的研究有时间限制” If species begin to go extinct faster than we can describe them如果我们描画生物的速度比不上生物灭亡的速度 then we might never know how much life Earth has to offer.那么我们就永远不知道地球养育了多少种生物 And after seen something like THIS, I don’t want to see that happen.在看过热带的风景之后 我不希望发生那样的事情 Stay curious.保持好奇 Thanks to prudential for sponsoring this episode.感谢保诚保险公司赞助本栏目 The time between when people think从人们打算存退休金 they should start saving for the retirement到真正开始存钱 and when they actually do is known as the action gap.这段时间间隔叫做行动间隔 According to a recent survey conducted by prudential,保诚最近进行的调查显示 the average American start saving for retirement美国人开始存退休金的平均时间 seven years later than they think it’s best.比他们认为最佳的时间晚了7年 That can cost you 410676 dollars in your life time.这会让人们多花410676元 I did that my head.这是我心算的结果 Another prudential study found that one in three Americans is not保诚的另一项研究称 三分之一的美国人 saving enough for their retirement.没有存够退休金 You can go to RaceForRetirement.com你可以去RaceForRetirem网站上 and see how the action gap affect you.看看行动间隔会怎样影响你 I hope you enjoy the first video from our trip to the Peru Amozon.希望你喜欢我们秘鲁亚马逊之旅的第一个视频 I should add that when it comes to explaining应当补充的是 关于为什么赤道周围 why there is more species near the equator,有更多物种这一问题 scientist aren’t totally sure what the right answer is yet,科学家还不能完全确定答案 but these are the best theories we have right know.但这些是我们目前已知的最好理论 Remember, that how science works.记住 科学就是这样 We gotta keep studying them,想要继续研究这些物种 which means we gonna make sure these species that you want study are still around.就要确保这些物种仍然存在 I have lots more video from Peru in the coming months.接下来几个月 我将陆续发布秘鲁之旅的更多视频 So stay tuned.请继续收看 A special thank you to rainforest expeditions for hosting us in Peru特别感谢热带雨林探险队接待我们 It was incredible experience,这是一段美妙旅程 and we cannot wait to share with you我们迫不及待地想和您分享 the rest of our peru adventure.接下来的旅程
  • 2021-10-17人类从哪里来?Picture human ancestry like a single chain of species: primitive to perfect,我们常把人类祖先想象成单一的物种链:从原始到完美 with a progression of all the apey-human things in between.两者之间是所有猿人的进化过程 Now take that picture, crumple it up and light it on fire.但事实并非如此 That’s not how it happened.单一进化链的想法应当付之一炬 Now we know we’re just one of more than two dozen human species现在我们知道 我们只是二十多个 that’ve walked the Earth…用双足丈量过土地的人类物种之一 well, probably walked.唔 应该有一部分能双足行走吧 Some even lived alongside us.有些古人类甚至曾与我们的祖先毗邻而居 So where do all those other twigs fit on our tree?这些古人类应该放在进化史上的什么位置呢 And what makes us… us?是什么让我们的祖先脱颖而出 成为如今的我们? This is us.这是人类 And this is our closest living relative.这是现存与我们亲缘关系最近的生物 Chimps aren’t our ancestors.黑猩猩不是我们的祖先 We share a common ancestor,我们有一个共同的祖先 and genetic studies say chimp and human histories但基因研究表明黑猩猩和人类的进化史 split around 7 million years ago.在大约700万年前就分道扬镳了 When I say “human” (with a lower case h) or hominin,当我说“人类”(小写h)或古人类时 I’m talking about all the species in here.我是泛指这里所有的物种 That’s where all the interesting things happened这才是所有有趣的事情发生的地方 that made us what we are today.正是这些事造就了今天的我们 We’ve unearthed thousands of ancient remains,我们已经出土了数千具上古遗骸 and not all belong to our ancestors.它们并不是全都属于我们的祖先 The challenge is sorting which of them我们面临的挑战是 lie on other branches–dead ends–on the evolutionary tree,如何区分其中哪些处于其它进化分支 and which are part of our story.又是哪些见证了现代人类的进化史 That story can be hard to follow,这个故事可能信息量很大 and it has a lot of characters…而且有很多人物…… and they all end up dead.他们最终都死了 And in the Game of Bones, you win when you die, and turn to stones在遗骸游戏中 当你死后变成化石时你就赢了 So what’s the oldest species in our family album?那么我们族谱中最古老的物种是什么呢 It’s hard to tell for sure.很难确定 As we look back in the fossil record,当我们回顾化石记录时 the distinctive features that make us human become less distinctive.那些让我们人类与众不同的特征变得不那么独特了 This one lived around the time chimps split off.乍得沙赫人生活在人类与黑猩猩分化的时代 It’s almost entirely ape-like,它几乎完全像类人猿 but with smaller canine teeth than chimps today,但犬牙比现在的黑猩猩要小 and a skull carried upright instead of at an angle,而且它的颈椎是直立而非前倾的 the way knuckle-walkers carry theirs.有点原始人的味道了 But our *ancestor*?但是我们的祖先呢 Can’t be sure.不能肯定 Jump ahead and we meet Ardi.往前看 我们遇到了地猿始祖种 Small ape brain, an upper body adapted to the trees,它的大脑很小 有着适应树栖生活的上半身 and a big toe that’s more like a thumb,还有一个更像拇指的大脚趾 but a pelvis shape that could have handled some bipedal movement–但是骨盆形状或许允许其进行一些双足运动 walking on two legs, some of the time.比如偶尔用两条腿走路 This makes sense when you think about it.仔细想想 这有道理 The first apes to hit the ground第一批走向大地的猿类 couldn’t learn everything when they got there.不可能直到下地才一下子学会所有东西 They’d get eaten.他们会被捕食的 They must’ve already been comfortable up on two legs,他们肯定已经习惯了双足站立 the way orangutans are.就像红猩猩一样 4.1 million years ago, we find strong knees that can hold weight.我们发现410万年前人类祖先就有能负重的强壮的膝盖 And by 3.7 million years ago, ancient humans on two legs, full time.到了370万年前 人类祖先已经完全依靠双腿行走了 We know this because they left actual footprints.从他们留下的真实的脚印中可以得证 The likely owner of those feet was this, Australopithecus afarensis.那些足迹可能是非洲南方古猿留下的 The most famous member of this species, Lucy,其中最广为人知的成员是露西 shows a ton of two-legged adaptations:她有很多适应双足行走的身体结构: a human-like foot,a short pelvis,一个类似人类的脚 一个短的骨盆 and a femur that angles inward for a smoother stride还有一个能使步幅更平稳的向内倾斜的股骨 There’s a good chance Ardi and Lucy aren’t our ancestors,地猿始祖种和非洲南方古猿很可能不是我们的祖先 but they show us that 3…4 million years ago,但他们表明 三四百万年前 evolution was already doing experiments on two legs.这两种猿类的双腿已经在进化了 At this point you might be wondering: Why walk?此时你可能会想:为什么要走路呢 Swinging from trees is fun!在树上摇荡多有趣! We know the earliest apes on our branch lived in forest areas,我们知道进化史上最早的类人猿生活在森林地区 where food is usually easy to find,在那里他们通常很容易找到食物 so tree-swinging and knuckle-walking are fine ways to get around.所以在树上摇荡和拳步行走是很好的行走方式 But a few million years ago,但是几百万年前 a changing climate turned African forests into grasslands气候的变化使非洲的森林变成了草原 where food was harder to find类人猿很难在这找到食物 so apes had to travel and innovate.所以他们必须迁徙和进化 Between 2 and 3 MYA, we hit a big gap in our family tree,两百万到三百万年前 我们的家谱出现了巨大的空白 but it’s at a key point on the path to becoming us.但这个空白正处于形成人类的关键时刻 In 2015, a new species was found, that might fit here,2015年 我们发现了一个可能适合这个时期的新物种 that might be a link between apes like Lucy and apes like us.它可能把像Lucy这样的类人猿和我们人类联系起来了 But we still don’t know exactly when it lived, so… yeah.但是我们仍不知道它确切的生存时间 所以…… Another question.另一个问题 It’s kind of a theme in paleoanthropology,这是古人类学的一个主题 every bone you find seems to make the story less simple.你发现的每根骨头 似乎都让故事变得不那么简单 So why all the gaps?那么 这些空白从何而来呢? If you’re an ancient ape who wants to be famous a few million years in the future,如果你是一个想在几百万年后出名的远古猿类 here’s some advice:这儿有些建议: Make sure you drop dead in soft sediment,确保你自己死在柔软的沉积物中 or maybe somewhere like a bog.或者死在像沼泽一样的地方 Try to get buried quickly, away from oxygen.尽量赶紧下葬 远离氧气 Then hope a river, glacier, or moving continent doesn’t sweep you away,然后祈祷河流 冰川或移动的大陆不会把你带走 and stay clear of wind and rain ‘til your skeleton is chemically transformed into stone.在你的骨骼被化学反应转化成石头之前 你要远离风雨 Finally, hope someone happens to dig you up.最后 希望有人能碰巧挖到你 You can probably see why fossils are so incredibly rare这下你可能明白为什么化石如此罕见了 yet we’ve still found enough to fill in most of the gaps.不过我们仍发现了足够多的化石来填补发展史上的大部分空白 But after that gap, the tree starts to come into better focus.在这一空白之后 进化史开始变得更加清晰 2.4 million years ago that’s definitely part of our family.240万年前的能人绝对是我们家族的一部分 Probably.应该是这样 Homo habilis wasn’t the first hominin to use tools,能人并不是第一个使用工具的古人类 but they really pioneered the whole maker movement.但他们确实是制作工具的先驱 1.8 MYA, this is definitely our relative180万年前 直立人绝对是我们的亲戚 Like, I’m almost sure.我几乎可以肯定 Homo erectus was one of the most successful human species of all time.直立人是有史以来最成功的人类物种之一 They were on Earth 8X longer than we’ve been so far.到目前为止 它们在地球上存在的时间比我们长了8倍 They were the first to cook their food,他们是第一个会烹饪食物的猿类 which fed their larger brains more energy.这给他们的大脑提供了更多的能量 And they were also the first to move out.他们也是第一批迁徙出去的人 Homo erectus made it as far east as China and Indonesia.直立人的足迹远至中国和印度尼西亚 One group even ended up on Flores island,有一群人甚至最终抵达弗洛雷斯岛 where a genetic twist would shrink them to Hobbit size.变异基因使它们缩小到霍比特人的大小 700,000 YA a group of Homo erectus back in Africa split into a new human species70万年前 一群非洲直立人进化成了弗洛里斯人 with brains nearly as large as our own,他们有着几乎和人类一样大的大脑 creating more advanced tools能创造出更先进的工具 Some of these humans migrated to Siberia.一些弗洛里斯人移居到了西伯利亚 Some, into Europe, where they became Neanderthals,还有一些弗洛里斯人在欧洲进化成了尼安德特人 an intelligent and mysterious species那是一个聪明又神秘的物种 whose way of life is being completely redefined…他们的生活方式正在被彻底地重新定义 but we’ll come back to them.但我们会回到他们身上 A little later, back in Africa, a new branch was budding off.不久之后 一个新的分支在非洲悄然诞生 The best branch.那是最好的分支 Our branch, Homo sapiens.我们的分支 智人 For 200,000 years, Earth has been home to humans20万年来 地球一直是 anatomically identical to you and me.与你我在解剖学上完全相同的人类的家园 It’s an incredible idea to look back and consider.回首往事 这简直令人难以置信 But even more incredible is that但更令人难以置信的是 until maybe 15,000 years ago, Earth was home ,at some times,直到大约15000年前 地球在某些时候 to other human cousins in addition to us是除我们以外的其他人类表亲的家园 We don’t know exactly how many human species我们不知道到底有多少人类物种 have decorated our family tree in all.在我们的进化树上有一席之地 How do we even draw lines between them我们如何在这几千万年的变化中 over 100s of thousands–millions– of years of change,在它们之间划清界限呢 and even some enter inbreeding甚至一些猿类会近亲繁殖 I told you it was Game of Bones.我告诉过你这是《遗骸游戏》 Tracing our story in reverse is full of回顾这棵参天大树 它充满了 dead end turns, gaps, and fossils we haven’t found yet.断枝 空白和我们尚未发现的化石 In fact, maybe a tree isn’t the right way to look at it.事实上 也许以进化树的方式看待它并不那么合适 Stephen Jay Gould said: human ancestry is more like a scraggly bush,斯蒂芬·杰·古尔德说:人类的祖先更像是一片杂乱无章的灌木丛 full of tangles and shadowy areas,到处都是混乱和阴暗的地方 and it just so happens we’re the only branch left.而我们恰好是剩下的唯一分支 Through our human ancestors,通过我们的人类祖先 we have a good idea on where we come from我们很清楚我们来自哪里 and what makes us who we are.以及是什么造就了我们 But the reason we’re the only humans left…但我们是仅存的人类的原因…… is another story altogether.完全是另一回事 And we’ll tell that story next time.我们下次再讲这个故事 Stay curious.保持好奇 This video is a part of a series of word doing all about this humans story.这个视频是关于人类故事系列的一部分 you could click there you could find a playlist with all of the videos.你可以点击那里 你可以找到所有视频的播放列表 And make you subscribe so you don’t miss the next chapter.记得订阅视频 以免错过下一章
  • 2021-10-17虎猫:自认为是猴子的猫The jungles of South and Central America are home to a tricky little mimic.中南美洲的丛林中住着一种狡猾的小型模仿者 These adorable predators rule the treetops with an overly fuzzy paw.这些可爱的捕食者凭借毛茸茸的爪子占据着树梢 This is the most arboreal cat in the world这就是世界上最爱在树上栖息的猫科动物 –the trickster of the trees, the Tamarin’s bane,——树上的魔术师 绢毛猴的克星 the Margay.长尾虎猫 不出名的小猫 The Margay, or Painted Cat,长尾虎猫 或者叫虎斑猫 is the middle child of the Leopardus genus,在美洲豹属中排行老二 fitting in between the smaller Oncilla, and the larger Ocelot.介于小斑虎猫和豹猫之间 If Ocelots are mini Jaguars,如果豹猫是迷你美洲虎 then Margay are mini Ocelots.那么长尾虎猫就是迷你豹猫 Ocelots can weigh up to 15 kilograms,豹猫重量可达15公斤 while a Margay will weigh at most four kilograms.而虎猫最多只有4公斤 Despite being roughly a third of the size,尽管虎猫的体型仅有豹猫的三分之一 a Margay can be hard to tell apart from an Ocelot,但人们还是傻傻分不清 but the big clue is their eyes.除了它们闪亮的大眼睛 Margays have giant, puss-and-boots-eyes that stand out much more than an Ocelot’s.虎猫有和靴子猫一样的大眼睛 比豹猫出众多了 While the Ocelot’s size and adaptability have allowed it to conquer a myriad of terrain,虽然豹猫的体型和适应性能让它征服很多地方 the Margay is a specialist.但是虎猫才是这方面的专家 And their area of choice?那它们选了哪儿? The Treetops.答案是树梢 Margays are one of the, if not the, most arboreal cats in the world.虎猫是世界上最喜欢在树上生活的猫科动物 Allowing them to conquer such a physically challenging habitat让它们征服如此具有体力挑战的领地 are a series of evolutionary adaptations是一系列的适应性进化 – first and foremost, their feet.– 首先是它们的脚 Jungle trees are full of twists and turns,丛林里的树弯弯曲曲 and only the most dexterous of species are able to navigate them with any sort of skill.只有最灵敏的动物才能驾驭它们 It’s this demanding habitat正是在这样极为苛刻的栖息地中 in which New World monkeys, with their prehensile tails and opposable thumbs, thrive.有着蜷曲尾巴 对生拇指的新大陆猴子茁壮成长 Similarly, Margays have evolved their own tools同样 虎猫也进化出它们自己的工具 to get around – they have ankles that can turn up to 180 degrees.它们的脚踝可以旋转180度 This, in combination with their sharp claws,这样再加上锋利的爪子 allows them to descend trees head first –它们就可以头朝下从树上下来 greatly increasing their agility in the tree canopy.大大提高了他们在树冠层的敏捷性 They also have very long tails它们还有很长的尾巴 which allow them to balance in the treetops –可以用来在树顶上保持平衡 a key tool in hunting their prey of choice – Tamarins and other New World monkeys.是捕捉猎物——绢毛猴和其他新大陆猴子——的重要工具 In order to traverse the jungle canopy with any speed,为了能够以任何速度穿越丛林的树冠 you have to be able to make decisions very quickly你必须能非常迅速的做出决定 and adapt to new situations at the drop of a hat.并立即适应新的情况 Branches may not lead where you expect,树枝可能不会通往你所希望的地方 and prey species may be more familiar with their territory than you are.猎物可能比你更熟悉它们的领地 If you’re not smart, they’ll outmaneuver you.如果你不够聪明 它们就会制胜 Margays are very intelligent, and while they are experts in navigating the trees,虎猫非常聪明 尽管它们是树上的穿梭专家 and can jump up to 3.5 metres horizontally,跳跃可达3.5米远 they know that sometimes it’s smarter to let the prey come to you.它们知道有时候让猎物亲自送上门是更明智的选择 These cats are tricksters.这些猫是骗子 Instead of chasing down prey, they’ve been known to mimic them instead.他们不是追捕猎物 而是模仿猎物 One cat was seen mimicking the vocalizations of a baby Tamarin – although poorly – and有只虎猫被观察到在模仿绢毛猴宝宝的叫声 尽管非常蹩脚 when the adults showed up to see what was going on, it pounced.当成年猴去看发生了什么 它就扑过去 While the jungle canopy provides a lot of different prey options,虽然丛林的树冠提供了很多不同的猎物 like bats, birds, and monkeys,如蝙蝠 鸟类以及猴子 they will venture more into the territory of their larger cousins, the Ocelot,它们会更冒险地进入它们表亲豹猫的领地 when the opportunity is right.当然是在合适的时机 This Margay has spotted something moving on the ground.这只虎猫发现地上有东西在动 A rat.一只老鼠 She starts to make her way down the tree.她开始往树下走 Having not seen the Margay descending from the canopy,没看到虎猫从树上下来 this rat’s day is about to get a lot worse.这老鼠的日子过到头了 The Margay silently advances, its massive paws help mask the sound of its approach.虎猫悄然靠近 巨大的爪子掩盖了它靠近的声音 She pounces.她猛扑过去 But this rat isn’t going down without a fight.但这只老鼠不会不战而降 The rat jumps, kicks, and bites, trying to ward off its attacker.老鼠又跳 又踢 又咬 试图避开虎猫的攻击 It looks like the rat might make it out alive.看来这只老鼠可能会活下来 But at long last,但最后 the Margay gets a hold of the rat’s neck and crushes its windpipe.虎猫抓住了老鼠的脖子 咬断了它的气管 A good day for the Margay is good night for the rat.虎猫的好日子建立在老鼠的小命上了 Margays are nocturnal, and usually spend their days asleep in the trees,虎猫习惯夜行 白天通常在树上睡觉 but this opportunity was too good to pass up.但这个机会实在是不容错过 With their giant eyes built for night vision,他们巨大的眼睛是为了夜视 and their giant paws built for climbing,巨大的爪子是为了攀爬 it’s easy to say that these are the cutest predators in South and Central America.可以说它们是中南美洲最可爱的掠食者 But something that makes them even cuter?但有什么让他们更可爱的吗? Their fur.它们的皮毛 Like their cousins,和它们的近亲一样 their coats are covered in dark rosettes and streaks它们的皮毛上覆盖着暗色的花结和条纹 meant to mimic dappled sunlight on the jungle floor.可以让它们模仿洒在丛林地面上的阳光 But they have an added feature, they have extra fuzzy fur, but no one really knows why.但它们还有一个额外的特征 就是毛茸茸的皮毛 没有人真正知道为什么 In fact, in Brazil, they are colloquially known as Gato Peludo, which means ‘extra furry cat’.事实上 在巴西它们通常被称为Gato Peludo 意为多毛猫 Unfortunately, this coat is one of the reasons why they are listed as a near threaten species.不幸的是 这种皮毛正是它们被列为濒临灭绝的物种的原因之一 Their coats can be a hot item on the black market, and thus虎猫皮毛在黑市上很抢手 因此 make Margays a popular target for poachers.长尾虎猫是偷猎者的捕猎热门对象 They also suffer much more so than their less arboreal relatives from deforestation.与近亲相比 树木砍伐给它们带来的损失更大 Massive areas in their range can no longer sustain them or their prey 受栖息地碎片化 森林砍伐以及城市化的影响 due to fragmentation, deforestation and urbanization,其生存的大片区域无法再养活它们或它们的猎物 and their populations are only healthy in the Amazon basin.它们的群落只有在亚马逊盆地中才正常繁衍 As we continue to segment their populations by dividing them with roads, farms and cities,随着人类不断用道路 农场和城镇分割它们的种群 their numbers will continue to decline.它们的数量将持续下降 We obviously love all animals here at Animalogic,动物逻辑的支持者显然都爱护所有动物 but I have a special spot for Margays.但是我们为虎猫准备了一个特殊的地方 After all, they’re cousins of my cat Nebula,毕竟它们是喵星人Nebula的表亲 so they’re practically family.所以实际上也是一家人 A few months ago,几个月前 Nebula got her first Pet Treater boxNebula得到了它的第一个宠物招待盒 and she’s been loving them so much that她太喜欢了 she begged me to get one for her friends.所以求我给她朋友也买一个 How could I say no to those eyes!我怎么能拒绝那双眼睛呢! Now her friends are enjoying all natural treats and toys, selected just for them.现在她和朋友们都享受着为她们挑选的天然零食和玩具 Both her canine and feline friends are enjoying boxes designed to fit their size,她的犬科和猫科朋友们都很喜欢为它们量身打造的盒子 and any allergies or dietary restrictions they might have.以及它们在饮食中可能的过敏源 It’s great for owners too.这对主人来说也很好 I’ve saved time and money在过去两个月中 over the last two months by subscribing to Pet Treater我通过订阅Pet Treater 节约了金钱和时间 and it gives Nebula and me something to look forward to.这给了Nebula和我一些期待 I have so many pictures of her pouncing all over her new treats and toys.我有好多她扑在新玩具上的照片 Go to Pettreater.com/animalogic and use your coupon code: Animalogic,登录这个网站 使用动物逻辑的优惠券吧 to get 50% off your first month of your subscription,订阅的第一个月可以打五折哦 and share your cute pictures with the Pet Treater community.还可以分享可爱的照片到Pet Treater Thank you, Pet Treater.感谢这份杂志 What should I talk about next?下一期该谈论点什么呢? Please let me know in the comments.请在评论中告诉我
  • 2021-10-17蝎子为什么会发荧光?Finding scorpions in the desert at night在夜晚的郊野找到蝎子 is surprisingly easy.十分容易 All you need is an ultraviolet torch你只需要一个紫外线手电筒就行 because scorpions are incredibly fluorescent.因为蝎子竟然会发荧光 Fluorescence means their bodies absorb ultraviolet light会发荧光意味着它们的身体吸收了紫外线光 and reradiate it in the visible part of the spectrum.然后再反射出可见光 They glow this bright neon green color.它们就会发出这种明亮的荧光绿 But scorpions aren’t the only animals that fluoresce.但蝎子还不是唯一会发荧光的动物 Jellyfish, amphibians, owls, and even platypus’水母 两栖动物 猫头鹰 甚至鸭嘴兽 glow under ultraviolet light.在紫外线光照射下都会发光 Part of this video is sponsored by Capital One Shopping.部分视频内容由Capital One Shopping赞助 More about them at the end of the show.在视频最后 将会详细介绍 I’m out here in the desert near Bakersfield, California,我现在是在加州贝克斯菲尔德市的沙漠中 looking for scorpions with Carl Kloock,和Carl Kloock一起寻找蝎子 a professor of biology at Cal State Bakersfield.Carl Kloock是加州州立大学贝克斯菲尔德分校的教授 He’s been researching scorpion fluorescence过去十多年中 for over a decade.他一直致力于蝎子荧光现象的研究 If you have a black light it’s really pretty easy.如果你有个紫光灯 就很容易找到 If they’re there, you’re going to spot them.如果附近有蝎子 你会发现它们的 [Derek] Does he look like he’s in a posture它的姿势看起来 to like defend himself?像不像在防守? – [Carl] Yeah, he’s not real happy. – [Derek] Okay.– 对 它可不太高兴 – 好吧 (man chuckling)[笑声] [Carl] I’m going to grab my high-tech我要去拿我的高科技 scorpion catching equipment here.蝎子捕捉器 It’s a tongue depressor with a yellow highlighter on it.这是一个压舌板 上面有一个黄色的荧光灯 So it fluoresces in black light.所以它在紫外线灯下会发荧光 – So you can see where it is. – [Derek] Got it.– 这样你就能看到蝎子在哪 – 明白了 (man chuckling)[窃笑声] [Carl] This technique is usually to put通常的技巧是 the vial behind him,在它后面放一个小瓶 then in front of him.然后在它的前面(戳一下) [Derek] That was impressive.这太神奇了 All right. Should we give it a shot?好了 我们来试一试? [Carl] Just gently pokes him back in.把它轻轻地向后戳进去 And they usually just kind of do a little然后它们通常会 side crab walk back.横着向后走几步 There you go, and just tilt it up.抓到了 稍微向上倾斜 [Derek] Unbelievable.竟然跑了 (man chuckles)[笑声] Unbelievable.怎么会呢 All right. I’m going to get him.好吧 我一定要抓住它 But why are scorpions fluorescent?那么为什么蝎子会发荧光呢? I’ve got about 12 hypotheses.我有大约12种假设 So you test them one at a time.然后逐个进行测试 [Derek] You’ve got 12 Hypotheses about why你有12种假设 the scorpions fluoresce?关于蝎子为什么会发荧光吗? More like six actually, I was being a little bit…实际上有超过6种吧 Almost all scorpions fluoresce.几乎所有蝎子都会发荧光 I haven’t seen it myself,我没有亲眼见过 but some that live at living caves they don’t fluoresce但是一些生活在洞穴里的蝎子不会发荧光 but it’s only like one very small group.但这仅是一小部分 All the other scorpions fluoresce.其他所有的蝎子都会发荧光 One possibility is just, this is a Relic Trait.一种可能是 这是一种遗留特征 It’s something they developed way back是最早登上陆地的蝎子进化出来的物质 when they first came out on land and just haven’t lost.只是这种物质一直都没有退化 A chemical that has another function这种化学物质有其他功能 that just happens to fluoresce.只是碰巧能发荧光 There are plenty of chemicals that fluoresce.有大量化学物质会发荧光 I mean, we have internal bodily fluids that fluoresce.我们身体里的体液就会发荧光 And clearly those are never exposed to UV light.但显然那些体液从来不会接触紫外线光 So the idea of having a function所以身体里某种物质导致发光的想法 for that fluorescence is kind of silly.就有点说不通了 This fluoresce is about the same color as a scorpion,这种荧光和蝎子的颜色相同 but clearly isn’t a scorpion.但显然不是蝎子本身发出来的 It’s actually a rock.实际上是一块石头 The color is a little off.颜色有点不一样 [Derek] But that is like, what is that?但是很接近了 那是什么? – It’s plastic from Walpole. – [Derek] Huh.– 这是来自沃尔波的塑料 – 嗯 You wanted to know if the scorpions were fluorescing你想知道是否蝎子发出荧光 in order to attract insects.是为了吸引昆虫 – Right. – [Narrator] So how did you test that?– 是的 – 那么你如何试验呢? What I did was I used preserved scorpions like these ones我用之前保存的蝎子 就像这些一样 and I took half of them and dip them in我取一半蝎子 让它们裹上一层 UV blocking marine varnish so they didn’t fluoresce.阻隔紫外线海洋清漆 这样它们就不会发荧光 And then I just used basically flypaper然后我就用普通捕蝇纸 and took those things outside and set them side by side把蝎子取出来 并排放在上面 and then found the number of flying insects然后观察飞虫的数量 that were caught in each.在每一块纸上各有多少 – [Derek] Okay. – [Carl] So we were outside in moonlight– 明白了 – 所以我们就在月光下 and I did the same experiment,做了同样的实验 both under the new moon and the full moon.分别是在新月和满月时 And so what I found from that was我的发现是 when there was a new moon,当出现新月时 there was no difference in the number飞虫的数量没有区别 of insects caught by the fluorescent无论是发荧光的蝎子所捕捉的 and non-fluorescent scorpions.还是没有荧光的蝎子 But under the full moon, there’s nice, bright UV light但是在满月时 紫外线光足够亮 available there was a difference区别就显现出来了 and the ones that fluoresce actually caught fewer insects.发荧光的那一组实际上捕捉到更少的飞虫 It seems kind of counterintuitive.这个结果好像和我们的直觉相反 So that tells me that my hypothesis was wrong.所以证明我的假设是错的 Which happens a lot.这种情况时有发生 Basically yeah, they’re not using起码我们知道了 它们不是用荧光 their fluorescence to lure insects.吸引昆虫 In fact, the fluorescence is a bad thing for them in terms实际上 这种荧光不利于 of their ability to catch flying insects, at least.蝎子捕捉飞虫 Let me ask you this.我再提一个问题 If you find that fluorescence is counterproductive如果你发现荧光 for the scorpion in some way,某种情况下对于蝎子来说起反作用 doesn’t that indicate that there这不是恰好表明 has to be something useful?它们身上有另一种东西起到积极的作用吗? Exactly. There must be something that counteracts that.就是这样 一定有一些东西与之相互抵消 – Sort of negative. – That negative, yeah.– 某种负作用 – 负作用 是的 Scorpions are really well adapted for what they do.蝎子非常擅长调整它们的行为 One of the cool things here is it scorpions厉害的一点是 are actually able to metabolize iron and nickel.蝎子能够代谢铁和镍 And in their pincer here在它们的钳这里 and on the tips of their claws,还有螯肢的尖端 they actually have basically iron to strengthen that.实际上有铁 让这些部位更坚硬 [Derek] Iron and nickel at the end of their tail?它们的尾巴末端有铁和镍? [Carl] Yeah. Yeah. You can see like the color here’s a little bit different是的 你可以看到这里的颜色有一点不同 and that’s because of the iron.就是因为这里有铁 [Derek] That seems very aggressive to me.听起来很吓人 One of the main things we’re interested in here我们现在最感兴趣的是 is how they see.它们如何看到事物 So I’ve seen two of their eyes.我看到其中两只眼睛 [Carl] So, those are the median eyes right there.是的 这是它们的中眼 [Derek] Those two dark spots.那两个黑点 [Carl] Yeah. There’s a cluster of three eyes right there.是的 这里还有三只 And of course on the other side, so they’re symmetrical.当然另一边也有 它们是对称的 So they have a total of eight eyes.所以蝎子共有八只眼睛 Can they detect the light with parts of their body它们可以用眼睛以外的身体部位 that are not eyes?来探测光线吗? Yeah. Actually they can.是的 它们可以 [Derek] In a 1968 experiment,在1968年的一次实验中 researchers put scorpions in half covered Petri dishes.研究人员把蝎子放进半遮挡的培养皿中 Then they exposed them to bright light and all the scorpions然后他们用强光照射 这时所有蝎子 quickly hid under the covered part of the Petri dish.快速躲进了被遮挡的器皿下 Then the researchers painted over the eyes of the scorpions.然后研究人员把涂料涂在它们的眼睛上 So they couldn’t see and repeated the experiment.在它们无法看到的情况下 再次进行实验 But when they turned on the light, 93% of the time,当灯被打开 有93%的几率 the blinded scorpions still scuttled over这些被蒙上眼睛的蝎子仍然会迅速移动到 to the covered side.容器被遮挡的一边 The finding was remarkable.这项研究的发现令人惊叹 Scorpions don’t need their eyes to detect light.蝎子不需要用眼睛来探测光线 They can sense it with their bodies.它们可以用身体感觉到光线 That showed that they have what’s called这表明 在它们的尾巴上 an extra ocular light sense in their tail.有一种被叫做眼外光感的功能 So they can detect light with their tail.所以它们可以用尾巴探测光线 They can’t form images, they can’t,在尾巴上无法成像 but they can detect light.但的确可以探测到光线 The tail of a scorpion can detect light?蝎子的尾巴可以探测光线? One hypothesis is that they use it其中一种假设是 它们发出荧光是为了 to communicate with one another.和另一只蝎子交流 The idea being that they use it to determine我的想法是 它们以此来确定 primarily whether or not是否 another scorpion out there在它们面前的另一只蝎子 is of the same species for mating.是适合交配的同一物种 One fairly low probability hypothesis还有一种假设 但可能性不大 is that they can use it as camouflage那就是 蝎子将其用作伪装 because they absorb UV light.因为它们吸收紫外线光 If they’re sitting on another surface that absorbs UV light所以如果它们停留在另一个能吸收紫外线光的表面 and you have an organism that sees in the UV light而有的生物能够在紫外线光中看到物体 like some owls and things like that can do,就像猫头鹰和其他有这种能力的生物一样 they would tend to blend in very nicely with that.那么蝎子会和它所在的表面恰好融为一体 So it’s a possibility,所以说这是一种可能 but not that many organisms see in UV但能在紫外线光下看到物体的生物不多 and not that many that eat scorpion, see in UV既捕食蝎子 又具备这种能力的生物也不多 so it doesn’t seem very likely.所以这种可能性似乎不大 – [Derek] You go for it. – [Carl] You want me to do it upclose?– 你来抓吧 – 你想让我来吗? – [Narrator] You do it. – [Carl] Close.– 你来吧 – 抓到了 Here you go. See?拿着 看到了吗? There you go, wow.这里 哇 One of the ideas is scorpions came out of the water另一种看法是 蝎子从水中来到陆地上 from Silurian period long time ago.是在很久以前的志留纪时期 And there was a lot more UV just in sunlight那时太阳之类的东西 紫外线更强 and things like that then, because we didn’t have因为我们没有臭氧层 an ozone layer, we didn’t have, you know,是的 当时的大气层 all these things that are blocking UV in our atmosphere now.没有用于阻挡紫外线的东西 And so the one of the idea is that所以另一种观点是 it actually acts as a sunscreen.蝎子发荧光的现象实际上是一种防晒作用 It’s way to absorb those damaging ultraviolet photons去吸收那些有害的紫外线光子 and convert them away into something然后再把这些光线转移到别的东西上 and basically keep them from penetrating into the body而不是让它们渗透进它的身体里 and causing damage.从而造成伤害 [Derek] Go in your hole.进你的洞里去吧 There you go.给你 You got him.你抓到它了 And then there have been some other ones还有一些其他的猜想 that are a little bit more out there.有着更多的可能 One of which being the one that I actually其中一个其实是我最终认可的 settled on at the end is that they use it那就是 它们身体发荧光的行为 as part of their sensory system to detect the presence是它们感官系统的一部分 of light in the environment.作用是探测周围环境中光线的存在 So this was the later experiment after I gave up所以这是在我放弃了最初的想法之后进行的实验 on the initial idea that said that didn’t work.之前的那个想法宣告失败了 So, all I really did in that one, very simple,我做的事情非常简单 put a scorpion in each one of these things here在每个这样的容器里放一只蝎子 and then put this under ultraviolet light然后把容器放在紫外线光下 and exposed it to ultraviolet light.让它暴露在其中 And so I measured how long they spent exposed我测试了它们暴露在紫外线光下的时间 versus unexposed and how many times和它们没有被紫外线照射的时间 they went back and forth.以及它们在两个区域往返的次数 [Derek] And you were testing scorpions你是想要测试 that were fluorescent and not fluorescent.发荧光和不发荧光的蝎子有什么区别 [Carl] Right. So what I did with that was I developed是的 因此我的做法就是 我发明了一种技术 a technique to remove, or at least reduce能够消除或至少能够减少 the ability of scorpions to fluoresce蝎子发荧光的能力 simply by exposing them for long periods方法就是让它们长时间接触 of time to ultraviolet light.紫外线光 So basically, you’re just kind of taking the chemical所以 你主要的做法就是 that is causing fluorescence in their exoskeleton消除它们外骨骼中导致发光的化学物质 and your photo bleaching.让它们褪色 [Derek] So you’re kind of breaking it down?你等于是在打破它们的防线? [Carl] So basically, you’re making the chemical所以你是在让这种化学物质 not be able to function properly anymore.不再能起作用 What we found is the activity levels changed significantly.我们发现 它们的活动水平发生了明显的改变 So when you exposed to UV light,当暴露在紫外线光下 the non-fluorescence scorpions acted like不发荧光的蝎子的表现 they were in the dark.就像它们并没有处于光线中 There was no difference between their behavior它们的行为没有什么不同 and the dark and in UV light.不论是在无光还是有光时 Whereas when UV light was present for the ones然而当紫外线光照射发荧光的蝎子时 that can fluoresce, they reduced their activity levels.它们的活动水平有所下降 [Derek] What’s the conclusion from that?结论是什么呢? [Carl] The conclusion from that结论就是 is that the fluorescents itself is acting as a way to,发荧光本身是一种 for them to detect the presence of ultraviolet light.探测紫外线光存在的方式 Another researcher by the name of Douglas Gaffin,一位叫Douglas Gaffin的研究者 came up with a great phrase for it.为该现象提出了一个很好的说法 I wish I’d come up with the phrase, but I gotta give credit.我真希望我也能想出那样的词 但我做不到 He calls it, a whole-body photon detector.他称之为 全身光子探测器 So it’s part of their sensory system.因此这属于它们感官系统的一部分 What we don’t know is why they want我们还不知道的是 它们为何 to detect ultraviolet light so badly对探测紫外线光的需求如此强烈 that they’ve turned their whole body into a photon detector.以至于把自己整个身体变成一个光子探测器 The suspicion is that it has to do with determining我们猜测 这决定了 whether or not they should come out at night.在夜晚它们是否应该出来 [Derek] The idea is when UV light hits道理是 当紫外线光照射蝎子的身体 a scorpion’s body, it fluoresces and the tail detects它开始发荧光 它的尾巴开始探测周围 this emitted green light alerting the scorpion这种绿光向蝎子发出警示 that it is exposed so it searches for cover.它暴露了 然后它就会寻找掩护 [Carl] Scorpions are good at starving for long periods of time.蝎子擅于长时间忍受饥饿 They don’t need to eat that often.它们不必经常吃东西 And coming out and foraging is dangerous for them.并且外出和觅食对它们来说都是危险的 And so they don’t like to come out when it’s a moonlit night.因此它们在月光明亮的晚上不喜欢外出 Typically the only ones you’ll find out in the full moon通常 在满月的夜晚你唯一能看到的 are the ones that are really hungry, really need food.是那些饥饿难耐 需要食物的蝎子 If they’re well fed, they’ll stay down.一旦它们吃饱了 它们便再次躲起来 So they’re using that as basically their cue所以它们用这样的方式作为一种信号 in the environment and saying, you know,提醒着它们 okay, this is how bright it is.这里的光线强度就是这样了 So that’s a cue as to how likely I’m being preyed upon.这就预示着 我有多大可能被捕食 And then here’s how hungry I am.然后我还得看看我有多饿 That’s a cue how badly I need to get out and get some food.这提示我 我有多大的需求去寻找食物 – [Derek] Right. – [Dr. Carl] And then the trade off between those two– 没错 – 然后两者相权衡 is basically should I go out tonight决定了我今晚应该出去 – or should I stay in my hole. – [Derek] Yeah.– 还是待在洞里 – 是的 (techno sound)[电子音乐声] If you like overpaying when you shop well,如果你在购物时喜欢超额消费 then don’t listen to this next part.那么不要听接下来的内容 But if you want to save money, then keep watching.但如果你想省钱 请你认真看 Because this portion of the video is sponsored因为这部分视频内容 by Capital One Shopping, a free browser extension由Capital One Shopping赞助 这是一个免费的浏览器扩展 that will automatically find the best deals它可以在你网购的时候 when you shop online.自动找最划算的方式 It’s just two clicks to install只需要点击两次鼠标即可安装 and it works on all major browsers.所有主流浏览器均可使用 Then whenever you shop, it’ll work away in the background,在你购物时 它会在后台持续工作 comparing prices and testing coupons对比价格 检测优惠券 to make sure you never overspend on an item again.确保你不再花冤枉钱 As much as I want to save money,我想尽可能多地省钱 searching for bargains and coupon codes is a big hassle但寻找特价品 优惠券码 同样是件麻烦事 and Capital One Shopping lets you get the best dealsCapital One Shopping给你最划算的方案 without having to waste any of your time不需要浪费你的时间 finding those deals in the first place.就能第一时间找到最优惠的价格 They all apply automatically at checkout.在结账时会自动生效 They even have their own shopping page他们甚至还有自己的购物页面 that gathers products from across different sites集合了不同网站的商品 and picks out the cheapest ones还可以挑选出最低价的商品 so you can shop directly for the best deals on the internet这样你就可以直接在网上买到最划算的商品了 and you don’t need to be a Capital One customer to use it.你不需要成为Capital One的客户 This extension is free for literally everyone.这个拓展对所有人免费 So you can start saving money right away.那么 你可以立刻开始你的省钱之旅了 I want to thank Capital One Shopping感谢Capital One Shopping for sponsoring this portion of the video.对视频内容的赞助 And I want to thank you for watching.感谢观看
  • 2021-10-17本视频是个谎言Time travel is confusing, and can have drastic effects.时空穿梭令人困惑 而且可能会带来极大的影响 Imagine a world where you were the last living grandson of Hitler.想象一个世界 在这里你是希特勒最后的孙子 You grew up reading and learning the terrible things that your grandfather did,从小到大你都在学习和了解你祖父做过的那些可怕的事情 and you realize that this isn’t what you want your family to be known for.而你不希望自己的家族因为这些事情出名 And so, you spend your entire life solving the issue of time.于是 你花了一辈子研究时空穿梭 Time only moves forward… that is until now.可时间只会向前……直到现在 After years of work, you finally achieve your life’s goal.经过多年的努力 你终于实现了自己的人生目标 You’ve built a fully functional time machine.你建造了一台功能齐全的时间机器 And so, you go back in time to 1930. You find and carefully kill your grandfather.于是 你回到1930年 找到祖父 然后悄悄杀了他 Congratulations, you’re a murderer…恭喜 你现在是个杀人犯了 but you’ve also prevented the death of tens of millions of other people.但你也让数千万人免于死亡 But, now since your grandfather no longer exists, neither does one of your parents,但既然你的祖父死了 也就没有你的父母 and subsequently, neither do you.接着 也就没有你了 So if you don’t exist, then who killed your grandfather?那么 如果你不存在 是谁杀了你的祖父呢 This is known as the Grandfather Paradox. It sounds absurd at first glance,这被称为祖父悖论 第一次听到感觉很荒谬 but on closer inspectation, you find out that’s in fact logical.但仔细检查一下时间轴 你发现这在事实上是合乎逻辑的 Does the timeline you are living in snap off into a new one,你进入了一条新的时间线 or have you literally changed the history forever?还是永远改变了历史呢? Well, it isn’t really history now, is it?你并没有真的回到过去 不是吗 You’re just impacting your new present.你只是在影响现在 If you were travel back to the modern day 2021, what might the world look like?如果你穿越到现代2021年 世界会是什么样呢 Would it even exist?它还存在吗 Paradoxes are all around us,悖论无处不在 and you would be surprised at how common they are in our day to day lives.你可能想像不到 悖论在我们日常生活中有多么常见 I’m sure everyone watch this vedio has been to the beach before,我相信所有观看本视频的人都曾去过海滩 and if you haven’t, well you should try it sometime.如果你还没去过 那么你应该去一次 The water is beautiful, and the heaps of sand make really nice sand castle.海水很美 沙子可以堆成美丽的沙堡 until the tides knock them over, and well ruin them.直到潮水将它们淹没并摧毁 But wait, what makes a “heap of sand” a heap of sand?等等 为什么“沙堆”被称为“沙堆” Let’s say this, this heap of sand contains 1,000,000 grains of sand.举个例子 一堆沙子有一百万粒沙 Let’s remove just a singal grain of sand我们拿出一粒沙子 Does it still remain a heap?那它还是一堆沙子吗 Yes? Well, how about I take out another.你认为是? 那我再拿出另一粒呢 And another? If your answer is still yes, then we must come to the conclusion that接着又拿出一粒 如果你仍然回答是 那我们可以得出结论 even after I take out 999,998 grains of sand, it still remains a heap of sand.即使我拿出999998粒沙子后 它还是一堆沙子 Let’s take a different approach.我们换个不同的方式 Let’s do it in reverse, starting with one grain of sand.反过来 从一粒沙子开始堆起 We go from one, to ten, to ten thousand. At what point does it become a heap of sand again?从一粒到十粒再到一万粒 什么时候它才是“沙堆”呢 We apply labels to so many things, mostly for visual purposes.我们给很多东西贴上标签 多数只是为了辨认 But in theory, things can get pretty confusing.但理论上 有些事物十分令人费解 The most expensive cruise ship in the world is named the Symphony of the Seas,海洋交响乐号邮轮是全球造价最昂贵的邮轮 and it cost nearly $1.5 billion dollars to create.花费将近15亿美元 The features aboard the ship include 22 restaurants,游轮上有22个餐厅 24 pools, an ice-skating rink,24个游泳池 还有一个溜冰场 and even a full-size basketball court.甚至有一个标准的篮球场 For that price, the ship better be original, a one-of-a-kind vessel.相对于造价来说 这艘船设计新颖 独一无二 After 3 years on the sea, it’s safe to say that this ship is still…in fact, original.航行3年后 可以肯定地说 这艘船仍然崭亮如新 But as we all know,但众所周知 things go bad, things break, and over time, things begin to need to be replaced.东西会旧 会坏 时间长了 就需要更换 So, let’s say in ten years, the Symphony of the Seas rennovates it’s ice-skating rink.假如10年后 海洋交响乐号邮轮要翻新溜冰场 20 years after that, the ship’s restaurants are all renovated.20年后 船上的餐厅也全部要翻新 Then, in 50 years, all the steel forming the ship is replaced with new steel.50年后 组成邮轮的钢铁也会换成新的 At that point, can we still call the ship original?这样的话 我们还能说这是一艘原装船吗 Is it still the original Symphony of the Seas?它还是最初的海洋交响乐号邮轮吗 What if all of the old parts that we took off from the ship假如用这艘船上所有拆下来的部分 were used to make an entirely new ship.建造另一艘全新的船 Which these of two ships would you like call the original Symphony of the Seas?那你认为两艘船中 哪艘才是海洋交响乐号邮轮呢 The one that had all its parts replaced?是这艘部件全部换新的旧船 Or the one that was made from all the replaced parts?还是这艘由原部件组成的新船 What makes something original?什么使东西保持原样? Humans are just like that ship.人类就如同那艘邮轮一样 If you look at a picture from when you were a baby and compare it with what’s you look like now.如果你将自己的童年照和现在的样子作比较 You would see a world of difference.You have new hair,new teeth.你会看到很多不同 你换了发型 换了牙齿 you’ve grown a little taller, got a bit heavier, and maybe you even changed complexion slightly.你长高了 变重了 甚至连你的肤色都稍微变了 So, are you original?那么 你还是原来的你吗 Now you might say “Oh, it’s your thoughts and actions that make you original person.”你可能会说:“哦 使你保持原样的是你的思想和行为” but most of us used to believe that an old fat guy flew around the planet ,但我们大多都曾相信有一个又老又胖的家伙在地球上飞来飞去 and somehow brought presents down all of our chimneys in a single night.设法在一个夜晚将礼物从我们家的烟囱送给我们 Some of you might have even believed that babies came from the store when you were a kid,当你们一些人还是个小孩的时候甚至会相信孩子是从商店里买来的 and unless you still believe those now, your thoughts and convictions have also changed,除非你现在还信这些 否则你的思想和信念早就变了 so what exactly makes you original? What makes you, you?那么究竟是什么让你保持原样 是什么让你仍然是你 It’s not so simple.这可不简单 Speaking of original, have you ever heard of the term anti-stratfordian?说到原创 你听说过莎士比亚的著作权问题吗 Yeah, me neither. However,是的 我也没听过 然而 these are people who don’t believe Williams Shakespeare wrote the works that were attributed to him.就是有些人不相信莎士比亚的作品是他本人所写 It might sound like a dumb hoax,这听起来有点像愚蠢的骗局 but people like Mark Twain, Helen Keller, Sigmund Freud,但像马克·吐温 海伦·凯勒 西格蒙德·弗洛伊德 and even Prince Phillip all believe this theory.甚至菲利浦·伊拉斯谟亲王这些人都相信这个看法 The argument they claim is that Shakespeare didn’t have the education or traveling experience他们的论据是 莎士比亚没上过学也没有旅行的经验来写这本书 to write the works that he did. But if Williams Shakespeare didn’t write the books, then who did?但如果威廉·莎士比亚没有写过这本书 那又是谁写的呢 The Bootstrap Paradox might just have the answer.祖父悖论可能知道答案 It’s the year 2109, and a young boy named William who was in love with the works of Shakespeare stumbled on a time machine.2109年 一迷上莎士比亚作品的名叫威廉的男孩无意中发现一台时间机器 So, as any normal person wouldn’t do,任何正常人都不会这么做 he got into the machine and set the time to 1610, the height of Shakespeare’s popularity.他进入机器 把时间调整到1610年 这是莎士比亚最受欢迎的一年 Upon his arrival, he went in search of the famous playwright in London where he was working at the time他一到达 就去这个年代莎士比亚工作的地方 寻找伦敦最著名的剧作家 The boy asked a few people, but no one knew where to find the great Shakespeare,男孩问了几个人 但没人知道去哪找伟大的莎士比亚 in fact, they had never even heard the name before.实际上 他们之前从没听说过这个名字 Confused and devastated, the boy didn’t know what was going on.这个男孩感到十分困惑且震惊 他不知道发生了什么 But then he remembered that he always carries a copy of Romeo and Juliet in his bag,但他忽然想起他总是在包里随身带着一本《罗密欧与朱丽叶》 because who doesn’t? Right?谁包里没放这本书呢 So he brought out this book, rewrote it and published it under the name William Shakespeare, in honor of his idol.于是 为纪念他的偶像 他拿起这本书重新写了一份并以威廉·莎士比亚的名字出版 But if there was no William Shakespeare to begin with,但如果一开始没有威廉·莎士比亚这个人 who wrote the Romeo and Juliet that he brought with him? This is the Bootstrap Paradox.是谁写出了他随身携带的《罗密欧与朱丽叶》这就是祖父悖论 An object or piece of information that is sent back in time essentially becomes trapped in一个物体或一组信息被送回过去 the past in an infinite cause-effect loop. It has no point of origin.本质上造成了一个物体被困在过去 没有可溯起源的无限循环 Now in our scenario, that boy is stuck in what is known as a “causal loop.” In the future,现在在我们的设想中 这个男孩陷入了一个“因果关系循环 ” in 2109 as a young boy, he’ll stumble on the Romeo and Juliet book again,在未来的2109年 一个小男孩会再一次读到《罗密欧与朱丽叶》 and the exact same sequence of events will happen again, and again, and again, forever.完全相同顺序的事情会再次发生 直到永远 This begs the question – how do we know that we aren’t just reliving what has already happened?不禁要问 我们怎么知道自己不是在重温发生过的事? How are we sure that, everyday we wake up, we’re not stuck in a causal loop as well?我们如何确定每天醒来不是因果循环呢? Because here’s the thing, if we were, we would never know.因为 问题就在于 如果是 我们绝不会知道 Although we can remember the past, we can’t remember the future,虽然我们记得过去 却无法记住未来 so we would never know if something that’s about to happen has already happened.所以我们不可能知道 将发生的事是已经发生了的 Deja Vu gets us pretty close, though. Literally translating to “already seen”,虽然Deja Vu已经很接近了 按字面意思翻译过来就是“已经见过” Deja Vu is the feeling that you’ve experienced the present situation before.Deja Vu是一种你觉得以前经历过现状的感觉 But what is Deja Vu isn’t just a feeling?但为什么Deja Vu不只是一种感觉呢 What if we are truky reliving that present event again and again.要是我们真正一遍遍重温现在的事情 会怎样 And we can only remember it in parts.我们只能记住一些片段 Because our brains just aren’t strong enough to retain all the information in the loop?因为我们的大脑不够强大 无法记住发生的所有信息 The older we get, the worse our observation skills become.我们越老 我们的观察技能就变得越差 Our brains feel like we already understand how the world works,我们的大脑认为我们已经明白了这个世界是如何运转的 and so we draw conclusions about things that we can never say for sure are true.于是 我们对自己永远不能确定的事得出结论 How do you know the light in the fridge is off if you’ve never seen it for yourself?如果没亲眼看见 你怎么知道冰箱里的灯灭了? If a tree falls in the forest and no one hears it, does it make a sound?若一棵树倒在森林里 没人听见 那它发出声音了吗 You can make assumptions, but you can never be certain. This paradox is called可以设想 但不能肯定 这种悖论称为“薛定谔的猫” “Schrödinger’s Cat”, and the way it was originally phrased is a lot more grim.这个原始表述的方式就更加残忍 Basically, you put a cat in a box with a poisonous gas and a radioactive atom that基本上 把猫放进装有毒气和放射性原子的盒子 has a 50% chance of decaying within the next hour. If the atom decays completely,在接下来1个小时中放射性物质有50%的概率会衰变 如果放射性原子完全衰变 it triggers the gas which then kills the cat. However, the radioactive decay is completely random,那么它就会释放毒气杀死猫 然而衰变是随机的 and so no one can tell when exactly that might happen.所以没人能告诉我们具体什么时候会发生 What is the state of the cat before Schrödinger opens the box? Is it dead or alive?薛定谔打开盒子之前猫的状态 它是死是活 Essentially,Schrodinger is saying that until the box is opened, the cat must be thought of as both alive and dead.基本上 薛定谔说直到盒子被打开 猫都应该是即死又活的 It exists in a blurred reality. When Schrödinger observes it, the cat fits into a single reality.薛定谔注意到这个模棱两可的事实 而猫只有一种可能 Who knows, maybe the other possibility happens in a parallel universe.谁知道呢 也许另一种可能发生在平行世界中 Until the box is opened, neither outcome can be certain.直到盒子打开 任何结果都是不确定的 Alright we went dark there for a moment, and as the saying goes, there’s a rainbow after我们黑屏一会儿 俗话说 风雨之后现彩虹 every storm, but is there? The rainbow only exists when we look at it, when you take your eyes away,但真的有吗 当我们看见彩虹才用证明它的存在 the rainbow ceases to exist. This is not a paradox, it’s just really fun to think about.当你不看时 彩虹便不存在 这不是悖论 思考这个真的很有趣 Rainbows are basically optical illusions formed by raindrops, the Sun, and the彩虹其实是由雨滴 太阳 我们看事物不同的角度 angle we’re seeing everything from. This is why you can never see the end of a rainbow;形成的视觉幻象 这就是你看不见彩虹尽头的原因 no matter how fast or far you move, the rainbow will always be the same distance away from you.不管你移动的多远多快 彩虹会与你保持相同的距离 While scientists give this explanation for the existence of a rainbow,当科学家对彩虹的存在做出解释 religious people attribute it to the work of a deity, a God.宗教人士会认为是神 上帝在起作用 But whether you believe in a God or you believe in nothing, this causes me to question things.但无论你是否相信上帝 还是什么也不信 这都让我对此产生疑问 It brings to mind the Omnipotence Paradox.这就出现了上帝悖论 Can an omnipotent being create a rock too big for themselves to lift? Think about it for a second.上帝能创造出一块连他自己都搬不动的大石头吗 想一下 If you say yes, then they aren’t omnipotent because there now exists something they cannot do,如果你回答能 这就说明上帝不是无所不能的 a rock they cannot lift. And if you say no,因为现在有一块上帝搬不动的石头 如果你回答不能 then how can they be regarded as omnipotent if they can’t do anything and everything?如果他们也有做不到的事情 那么他们又凭什么被认为是万能的呢 Well, if we ever find this omnipotent being, maybe they’ll also be omniscient,好的 如果我们曾找到全能的生物 可能他们真的是无所不知的 and finally put this paradox to rest. Until then, we keep searching.最后我们把这悖论放一放 接着 我们继续探索 Searching for knowledge, or learning, is a fundamental part of life. It’s what has探索知识或学问 这是人生最基础的部分 这是能让我们这种物种走这么远的动力 gotten us this far as a species. We saw the world around us, asked questions about how it works,我们看着周围的世界 思考它是如何运转的 得到答案后 got answers, and we learned, or at least this is what the scientific method describes to us.我们学到 或者至少从科学方法中了解到 But the truth is, we never learn anything new by asking questions, we only learn answers that但事实上 我们从来没有通过提问学到什么新东西 already existed. In the words of Socrates, “A man cannot search either for what he我们只学习已经存在的事情 苏格拉底曾说:“一个人不能去探索他知道或他不知道的事” knows or for what he does not know. He cannot search for what he knows — since he knows it,他不能去探索他知道的事—因为他已经知道了 there is no need to search — nor for what he does not know, for he does not know what to look for.”也没必要去研究他不知道的事 因为他不知道去研究什么 Which is a strange quote.这是一个奇怪的举例 because every scientific, technological,and philosophival brrakthrough因为我们实现的每一个科学 技术和哲学上的突破 we have achieved has come from asking questions, or has it.都来源于提问 或都有提问 A while back I made a video titled “the english language is a giant meme..”,回到我做的一个题为“英语是一个巨大的模因……”的视频 because… it is. But creating that video didn’t only open my eyes to the many confusions in因为……确实如此 但做这个视频不仅解决了很多我在语言中的困惑 the language, but it also kept my eyes open to finding even more discrepancies in the future.而且也开阔了我的视野 让我在未来找到更多的差异 The word autological refers to a word that describes itself.自体同源指的是一个词可以自我形容 Multisyllabic is multisyllabic, a noun is a noun, and English is English. Heterological,多音节是多音节 名词是名词 英语是英语 on the other hand, refers to words that do not describe themselves.换句话说 逆逻辑指的是一个单词不可以形容它本身 Blue isn’t blue, hyphenated isn’t hy-phenated, and triangle isn’t a triangle. Autological蓝色这个单词并不蓝 带连字符的词并不带连字符 三角形长得并不是三角形 is autological since it describes itself, but is heterological heterological?自体同源是自体同源的 因为它形容了自己 但逆逻辑的是逆逻辑的吗 If you say no, that means it describes itself, which means it is heterological.如果你回答不 这意味着它能形容自己 这说明它是逆逻辑的 But then if you say yes, that means it does not describe itself,但如果你回答是 这意味着它不能形容自己 which means it is heterological, the endless loop continues forever.这就表明它本身是逆逻辑的 无限循环永远持续 And you know guys, I have a confession to make: this entire video is a lie.你们知道吗 我要声明:这整个视频是个谎言 If that statement is true, then everything in this video is a lie,如果这个“声明”是真的 那么本视频的所有内容就是个谎言 including that statement, which means everything in this video is true. But if everything in the包括该“声明” 这意味着本视频的所有内容都是真的 video is true, then that statement must also be true, but if that statement is true, it isn’t.但如果本视频中的所有内容是真的 那么“声明”也是真的 但如果“声明”是真的 那本视频就是假的 You got it? Good.你听懂了吗 很好 Is anything I said true? Is anything truly real? I’ll let you decide on that one.我说的对吗 所有的是真实的吗 这由你决定 Besides…除此之外…… Time travel is confusing, and can have drastic effects.时空穿梭是令人困惑的 还会产生极大的影响 This video was sponsored by Brilliant. If this video has taught you anything,本视频由Brilliant赞助播出 如果看了这期视频让你有所收获 it’s that information can be powerful. And if you’re not familiar with them, things like the这是个很棒的消息 如果你还不太熟悉 Bootstrap Paradox essentially trapping information in time can be a bit confusing to understand.像祖父悖论这样本质上把信息困在时间里的 可能有点难以理解的内容 We all learn things differently, what do you think is the best way to learn something?我们每个人的学习方法不同 你认为学习的最好方法是什么 we all learn things differently我们有不同的学习方式 Lectures? Memorizing formulas? Doing the odd-numbered questions听讲座 背公式 在数学书上做奇数问题 in your math textbook? Ok, no, absolutely not.好吧 不是 当然不是 Now, I could show you a bunch of research that shows what the best methods for learning are,现在 我可以向你展示一大串研究显示最好的学习方法是什么 but let’s be honest — we all know the best way to learn something new is by doing it.但说实话 我们都知道最好的学习方法就是实践 Brilliant is a website and app built around this idea: you learn best while doing and solvingBrilliant是基于“实践出真知”这一理念的网站和软件 things in real-time. The good thing is, you don’t need to memorize long messy formulas and endless好处是 你不需要背复杂的公式和无数的事实 facts — just pick a course you’re interested in and get started. There’s over 60 courses on只要选择一门你感兴趣的课程 然后开始上课 在Brilliant上有60多个课程 Brilliant, and many of them include paradoxes just like the ones I covered in this video.其中就包括像我在本视频中提到的悖论 Brilliant has something for everybody — whether you want to start with the basics of math,Brilliant适合所有人 不管你想学基础数学 science, and computer science,科学还是计算机技术 or dive into cutting-edge topics like Cryptocurrency or Quantum Computing.或加入最前沿的课程像加密数字货币和量子计算 If you’re interested and think you’d benefit from using Brilliant,如果你对此感兴趣 认为能从Brilliant中获益 head to brilliant.org/aperture and you can sign up for free. You’ll also get 20%可以前往brilliant.org/aperture免费报名 off a premium subscription that’ll allow you take every single course Brilliant has to offer.你还可以免除20%的额外订阅费 可以学习Brilliant上的每个课程 Let’s all continue growing in 2021 with Brilliance.让我们在2021年和Brilliant 一起成长 You’ll be supporting yourself and my channel at the same time.你可以在看我的频道的同时获益

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