本字幕由 YYeTs人人影视 原创翻译制作 仅供学习 禁止用于任何商业盈利行为 更多影视更新 请登陆 www.YYeTs.net
■
大家好 Hello.
我是斯蒂芬·霍金 My name is Stephen Hawking.
物理学家 宇宙学家 Physicist, cosmologist
还可以说是一个梦想家 and something of a dreamer.
尽管我行动不便 说话要借助电脑 Although I cannot move and I have to speak through a computer.
但在精神世界中 我是自由的 In my mind, I am free.
自由地去畅游宇宙 Free to tour the universe
讲述终极的宇宙故事 and tell the ultimate story.
讲述一切的故事 The story of everything there ever was.
从宇宙的起源 From the moment the cosmos began
到我们世界的诞生以及其间一切 to the creation of our world and everything in it
再到遥远的未来和宇宙的尽头 and beyond to the far, far future and the end of the universe itself.
这是一次穿越时空的旅行 A journey through all of space and all of time.
一起去探索吧 Check it out.
与霍金一起探索宇宙 一切的故事
翻译：yank121 amyiceman 点点点 取子小Q
■
初校：amira 精校：阿橙 时间轴：水水
■
后期：鱼骨头 总监：阿橙
■
我花了大量时间来思考宇宙 I spend a lot of time thinking about the universe,
却从未感到过厌倦 but I never get bored.
毕竟 这是一片非凡的领域 After all it's a pretty extraordinary place.
这就是宇宙 This is the cosmos.
浩瀚无际 And a very large scale.
每一个小光点都是一个完整的星系 Each tiny point of light is an entire galaxy.
每一个星系都拥有多达四千亿颗恒星 Each a cluster of as many as 400 billion individual stars.
只有通过最新的超级计算机 This view of the universe is only possible
才看得到这样的宇宙场景 due to the latest super computers.
它是如此的星光灿烂 I find it indescribably beautiful.
数十亿无以计数的星系形成了一张巨网 Uncountable billions of galaxies forming a vast web
向着四面八方延伸出去 stretching away in all directions.
而且 有一个事实我从未忘怀 What's more, I never get over the fact
那就是 在这广袤无垠的宇宙中 that within this massive universe
存在着一个极其普通的螺旋星系 lies one perfectly ordinary spiral galaxy.
在这个星系中存在着一颗平凡的金色恒星 Inside that galaxy exists a commonplace yellow star.
围绕着它的 是八颗行星 Orbited by eight planets.
在其中一颗行星上 生存着一个物种 On one of those planets lives a species
他们刚刚了解到宇宙有多么奇妙 that is only just worked out what a remarkable place the universe is.
这就是我们 人类 Us.
我们在上个世纪里对宇宙的探索发现 We've discovered more about the cosmos
达到了人类历史上前所未有的程度 in the last century than in all previous human history.
终于 我们开始着手破解那些 Finally we are solving the basic mysteries
困惑祖先二十多万年的普遍神秘现象 that have perplexed our ancestors for at least 200,000 years.
最吸引我的莫过于 What I like above all is
事实本身是如此地惊险迷人而又出人意料 that the facts themselves are both breathtakingly elegant and surprising.
我们生存在宇宙赠予我们的环境中 We are living just as it donates us
地球 以及我们身边的一切都源于恒星 that the earth and everything around us was made by the stars.
甚至是构成你睫毛的原子 Boiling fantasies of hydrogen gas like our sun
都源于同太阳一般 充满氢气的炽热球体 made even the atoms in your eyelashes.
我们计算出宇宙的古老程度几乎无法想象 We've worked out that the universe is almost unimaginably ancient.
大约存在了140亿年 About 14 billion years old.
而宇宙也还会继续存在至少两个这么久 And that it will continue to exist for at least twice that long.
但无需怀疑 But without a doubt,
最美妙的事实莫过于整个广袤的宇宙 the most remarkable fact of all is that the entire enormous universe,
所有无以计数的星系 all the innumerable galaxies
甚至是时间空间 以及自然力量本身 even time and space and the forces of nature themselves,
都源于虚无 终成宇宙 simply materialized out of nothing.
我认为 现在是个适合生存的好阶段 So now is a good time to be alive, I think.
我们或许不过是这颗小小行星上 We may only be an advanced breed of monkey
较为高等的猿类 living on a small planet,
但能够对宇宙整体的思索 but we are able to contemplate the universe as a whole
让我们变得与众不同 which makes us very special.
我的目标总是很简单 My goal has always been simple.
探索宇宙如何运行 以及它究竟是如何产生的 To work out how the universe works and how it exists at all.
幸运的是 指向答案的线索众多 Luckily there are clues everywhere
其中最重要的一个线索就我们的头顶上方 and the most important one is right above our heads.
仔细观察每一片夜空 Examine any patch of the night sky.
即便是看似针尖大小 你也会有所收获 Even one as small as the head of a pin and this is what you will find.
这只是星系巨网中的一小部分 A tiny part of the vast web of galaxies.
还不到能从地球上看到的宇宙的百万分之一 It's less than a millionth of what we can see of the cosmos from our little planet.
即便如此微小的样本也足以找出一条线索 But even this tiny sample is enough to find a clue,
一个了解过去 现在 甚至是未来的关键 the key to the past, the present, and perhaps the future too.
即从地球望向太空 The clue is that seen from earth,
所有遥远的星系都微泛红光 all these distant galaxies are slightly red in color.
它们的样子与我们透过玫瑰色镜片 They appear almost as if
看物体时非常相似 we were looking through rose-tinted glasses.
就是这样的红色向我们揭示了 It's this very redness that reveals
宇宙是如何诞生的 how the universe was born.
为究其原理 And to show you why,
我需要笔直的公路和噪音很大的汽车 I need a straight road and a noisy car.
请听汽车经过时的声音 Listen to the sound as it passes by.
随着汽车的接近 引擎音调升高 As the car approaches, the pitch of its engine rises.
随着汽车的离开 引擎音调则降低 As it goes away, the pitch of its engine falls.
这种现象叫做多普勒频移 This phenomenon is called a Doppler Shift.
这也同样适用于光 And the exact same thing happens with light.
如果肉眼对颜色非常敏感 If our eyes were most sensitive to color
人们便可以看到 we could see that the car
汽车接近时 实际呈微蓝色 is actually very slightly blue as it approaches,
而离开时 则呈微红色 and very slightly red as it goes away.
太空中的一切也同样遵循此规则 The same rules apply in space.
所有遥远的星系 看上去都是红色的 All distant galaxies are slightly red in color
根据这一基本物理规则 So by the exact same piece of basic physics
它们肯定也都在渐行渐远 they must all be moving away too.
事实上 整个宇宙都在膨胀 In fact, the whole universe is expanding
向着四面八方 越来越大 in all directions, getting bigger and bigger
就像一个充气气球 like a balloon inflating.
我承认这听上去有些奇怪 I admit this sounds strange,
但对宇宙学家来说 这就像是中了头彩 but to cosmologists it's like winning the lottery.
因为要想探索宇宙的起源 Because to work out where the universe came from,
我们只需让时间停止 并使时光倒流 all we need to do is to stop time and make it run in reverse.
回到远久之前 Rewind far enough
回到万物皆为一体的时候 and everything gets closer together.
紧密一体的时候 A lot closer together.
所有的星系 All the galaxies,
实际上 每一个物体 in fact, every single thing
都汇聚于某个点 converges to a single point.
137亿年前 一切起源的瞬间 The start of everything, 13.7 billion years ago.
事情就是这么简单 So it's quite simple really.
根据线索 我们可以推断出 Follow the clues and we can deduce
在很久很久之前 that a very long time ago,
宇宙初现雏形的场景 the universe simply burst into existence.
这就是 宇宙大爆炸 An event called the Big Bang.
不过在我们痴迷于爆炸和噪音之前 But I'm afraid we have to stop a moment
我要先在这里停一下 before we get carried away by fire and noise.
在一切开始之际 At the very beginning,
宇宙大爆炸实际发生于完全黑暗之中 the Big Bang actually happened in total darkness,
因为那时 光并不存在 because light didn't exist yet.
要想看到它 To see it,
我们就需要有某种宇宙夜视能力 we would have needed some kind of cosmic night vision.
但即使这样 But even this,
想要从外部来观看也是不可能的 a view from the outside is impossible.
这听起来还是有些奇怪 Again, it sounds strange,
但在那时 空间也同样不存在 but space didn't exist then either.
所以根本就不存在外部 So there was no outside.
宇宙只有内部 The only place there was was inside.
早期的宇宙的确是不同寻常 This early universe was a very strange thing indeed.
对于它 我还抱有强烈的好奇心 There is still much I dearly love to know about it,
但时间或空间的标准概念在这里并不适用 but standard concepts of time or space don't really apply.
它只是一团微小的极端高温能量雾 It was just a very tiny ultra hot fog of energy.
然后 它开始膨胀 Then it expanded
释放出巨量的辐射光 with a tremendous flash of radiation,
从不到原子那么小 膨胀到橘子那么大 from smaller than an atom to about the size of an orange
只用了不到万亿分之一秒 in less than a trillionth of a second.
其过程极其短暂 Almost no time at all.
宇宙就在膨胀中产生了 The universe simply inflated into existence.
不断延伸 不断展开 Unfolding, unfurling,
随着时间的流逝 不断膨胀 逐渐冷却 getting bigger and cooler with every passing moment.
在一百秒之内 Within 100 seconds,
就已经膨胀到太阳系的大小 it was as big as our solar system.
越过了数万亿英里 Trillions of miles across.
在这个过程中 While this was happening,
纯粹的宇宙能量开始冷却并创造出了物质 the pure energy of the cosmos began to cool and create matter,
形成数万亿无以计数的次原子微粒 in the form of countless trillions of subatomic particles.
它们是宇宙中最先出现的东西 The first stuff there ever was.
这些微粒中有一半是由物质构成 Half these particles were made of matter,
那是与构成人体相同的物质 the same kind of stuff which makes us.
其余则由物质的对立面构成 The rest were made of the opposite of matter,
即反物质 stuff called antimatter.
当它们相遇时 会互相毁灭 When the two meet they destroy each other
释放出能量之光 in a flash of energy.
宇宙的形成看似是一个破坏性的过程 It seems as if building the universe is a pretty wasteful process.
幸运的是 物质略多于反物质 Fortunately there was just a bit more matter than antimatter.
仅有约十亿分之一的微粒存活下来 Just one in a billion particles of stuff survived.
这对我们来说是幸运的 Which was lucky for us.
因为残存的微粒构成了我们如今的宇宙 because that residue is what our present day universe is made of.
可以说我们是宇宙大爆炸烟尘的衍生物 You could say we are made of the smoke of the Big Bang.
在宇宙诞生十分钟之后 By the time the cosmos was 10 minutes old,
其直径就已经达到数千光年 it was already thousands of light years in diameter.
在那之后 一切又扩散并冷却了近33万年 After that, everything spread out and cooled for about 330,000 years,
直到最终大雾散去 宇宙变得清晰可见 when finally the fog cleared and the universe became visible.
这便是一切的开始 So that's how everything got going,
是个非常美妙的故事 which I think it's a pretty fantastic story
且或许比我们祖先们所提出的各种解释 and probably much stranger than anything our ancestors
听起来更加离奇 just came up with by way of an explanation.
但接下来发生的事情 But the next thing that happened,
壮观程度是有过之而无不及 well, that's pretty spectacular too.
你所看到的是极速快进版的宇宙 This is the universe seen in extreme fast forward.
在不到一分钟的时间内 All 14 billion years
将宇宙140亿年间的变化纵观眼底 in less than a minute.
它揭示了宇宙是如何从一团气体 It shows how the universe changed from the crowd of gas
发展为充满千亿星系 into a place filled with perhaps 100 billion galaxies,
以杂乱的舞步旋转着的空间 swirling in a vast chaotic dance.
我喜欢引导大家去思考 What I love to get people thinking about
这一切都是由一个个原子组合而成 is that all this had to be built, atom by atom,
浩大的太空工程 celestial engineering on a spectacular scale.
那究竟是什么开启了宇宙的时钟呢 So what drove this cosmic clock work?
我认为正是万有引力 I would say it was the force of gravity.
万有引力的概念 The idea of gravity
是由艾萨克·牛顿爵士提出 was worked out by Sir Isaac Newton,
早在17世纪 who had the same job as me
他就在剑桥大学担任同我相同的职位 here at Cambridge University, back in the 17th century.
当一颗苹果落在他头上时 他受到了启示 It supposedly donned on him when an apple fell on his head.
苹果让他意识到了万物相互吸引 The apple helped him realize that all effects attract each other.
而且质量越大啊 引力越强 And the greater the mass, the stronger the pull.
这些苹果受到了地球的吸引 These apples are attracted to the earth
尽管你肉眼无法看见 and although you can't see it,
但地球也向苹果的方向轻微移动了 the earth moves very slightly up towards the apples.
一切都因为万有引力的存在而聚集在一起 All things come together through the power of gravity.
万有引力早在宇宙大爆炸时期就已产生 Gravity was created in the Big Bang
并自那时起一直发挥作用 and has been at work ever since.
是万有引力使得你 我以及苹果都能保持在地面 It's what keeps you, me, and apples stuck to the earth.
在早期的宇宙中 In the early universe,
万有引力的影响比现在大很多 gravity had a much bigger role to play.
大爆炸之后 宇宙仅仅是一片雾气 Right after the Big Bang, the universe was just gas,
在空间中近乎完美地延展开来 almost perfectly spread out throughout space.
在接下来的2亿年里 Over the next 200 million years,
万有引力开始将雾气集中起来 gravity began to pull the gas back together
产生了万物演变始于的最初结构 to produce the very first structures from which everything else would grow.
但即使是这也不是真实情况 But even this very nearly didn't happen.
若不是宇宙幸运地遇到另一件事情 If it weren't for another stroke of cosmic luck,
就根本不会存在你 我 恒星 there would be no you, no me, no stars
行星 以及其他的一切 or planets or anything at all.
我们知道这些 是因为在1982年 We know this because in 1982
包括我在内的一群科学家 a group of scientists including myself
花了整整三周的时间才将此一探究竟 spent three solid weeks working it out.
尽管计算过程繁复 Although the calculations were hard,
但证明我们的发现却很简单 demonstrating what we discovered is easy.
首先 我需要一块像这样的水平地板 First, I need a nice flat floor like this one, for example.
这里是我所在大学的餐厅 This is the dining room in my college.
我将用无以计数的钢珠覆盖地面 I'm going to fill the place with lots and lots of ball bearings.
这些钢珠代表着早期宇宙中的物质 These balls represent the matter of the early universe,
即均匀扩散到广袤宇宙之中的稀薄气体 a thin gas spread out evenly across the vast cosmos.
这时 好运来了 Here's where luck comes in.
如果他们彼此间距离相同 If they are all the same distance apart,
每个钢珠在所有方向上 gravity pulls each ball
受到的万有引力大小是相同的 the same amount in all directions.
它们会相当均衡地排列开来 They stay perfectly aligned
什么都不会发生 and precisely nothing happens.
幸运的是 宇宙基本规则之一便是 Fortunately, one of the basic rules of the universe
万物皆不完美 is that nothing's perfect.
世间不存在十全十美 Perfection simply doesn't exist.
早期宇宙存在着微小的不平衡 The early universe had a tiny unevenness
仅移走五颗钢珠就能再现情景 that can be simulated by removing just five ball bearings.
变化看似不足为奇 It may not look like much has changed,
但对于万有引力来说 but to gravity,
这些缺失的钢珠却创造出了巨大的机会 those missing balls create a giant opportunity.
引力在某一方向上作用更强 Gravity now pulls more strongly on one side of some of the bearings.
无数钢珠中微小的不规则 The tiny irregularities in the sea of ball bearings
给了万有引力发挥作用的机会 have given gravity something to sink its teeth into.
这正是刚才讲到的年轻的宇宙所发生的事 And this is exactly what happened back where we left the young universe.
部分早期的雾气要比其他部分略微稀薄一些 Parts of the sea of early gas were ever so slightly thinner than others.
较为稀疏的区域就像是钢珠之间的空隙 The less dense areas were like the gaps between the ball bearings.
较为密集的雾气部分 The denser parts of the sea of gas
则在万有引力作用下凝聚在一起 where gravity was having its way clumped together.
也正是在这些区域里 And it was in these areas
才汇聚成所有的恒星和星系 that all the stars and galaxies would fall.
宇宙向形成今天的绚丽多彩迈出了第一步 The cosmos had taken its first step towards the beautiful place it is today.
都归功于宇宙的不规律 瑕疵以及缺乏秩序 All thanks to irregularity, imperfection, a lack of order.
所以下一次 如果有人抱怨你犯了错误 So next time someone complains that you have made a mistake,
告诉他这或许是件好事 tell him that may be a good thing
因为如果没有瑕疵 你我都将不复存在 because without imperfection, neither you nor I would exist.
135亿年前 宇宙主要由氢气构成 13.5 billion years ago, the universe was mostly hydrogen gas
万有引力发挥其作用 with gravity doing what gravity does
缓慢地将氢气汇聚成广阔的云层 which is to slowly pull it into vast clouds.
氢气是最简单的气体 Hydrogen is the simplest of gasses.
却有一种罕见的特性 But it has a very special property.
它是个巨大的能量来源 It's a tremendous source of power.
将氢气加热至约一千万度 Heat hydrogen to around 10 million degrees
它便产生出能够使恒星发光的能量 and it begins to produce the energy that makes the stars shine
并为宇宙提供温暖和光亮 and supplies the universe with warmth and light.
为进一步理解 To see how this works,
让我们想象可以在地球制造一颗小恒星 let's imagine we can make a small star here on earth.
首先 我们需要足够的氢气 First, we need plenty of hydrogen gas,
最好能充满整个体育场 about a sports stadium full would be perfect.
接着 想象将氢气压缩 Next we need to imagine squishing this hydrogen together,
就像太空中的万有引力那样 just as gravity does in space.
伴随着氢气的压缩 As the hydrogen compacts,
气体原子逐渐相互排斥 the atoms of gas starts bouncing off each other
温度开始上升 and the temperature begins to rise.
在压缩至足球大小时 By the time it's compressed down to the size of a soccer ball,
氢气到达临界的一千万度 the hydrogen reaches the critical 10 million degrees.
核聚变便开始了 And a process called nuclear fusion begins.
氢开始聚合到一起 The hydrogen starts to fuse together,
生成一种新的更重的物质 氦 making a new, heavier material, helium.
通过一步步微小的撞击和摩擦 With every step of this tiny bump and grind,
一些物质转变为纯粹的能量 some matter gets converted into pure energy.
我们创造了一个微型恒星 We have created a miniature star.
当然 如果这是真正的实验 Of course if this was a real experiment,
你绝不会想靠近它 you wouldn't want to go anywhere near it.
如此小的恒星也足以释放出毁灭性的能量 The energy given off even from a star this small would be devastating.
追溯到宇宙初期 Back in the early universe,
同样的过程第一次发生了 the same process happened for the first time
只不过规模远大于此 on a much, much bigger scale.
数百万年来 万有引力压缩氢气云团 Gravity compressed the hydrogen gas clouds over millions of years
以至中心深处 until deep in the center,
氢气达到足够使聚变发生的高温 the hydrogen became hot enough for fusion to occur.
伴着耀眼的光芒 第一颗恒星诞生了 The first star burst into light,
其能量倾入广袤的宇宙 pouring its energy into the vast universe,
这正是自然法则 a product of the laws of nature
和宇宙大爆炸残留物的产物 and the raw materials left over from the big bang.
它比太阳大了近一千倍 It was almost 1,000 times bigger than our own sun
灼烧呈深蓝色 and burned a deep blue.
此外 这个恒星不久就有了同伴 What's more, this star soon had company.
恒星如雨后春笋般涌现出来 The stars were turning on.
太阳如今正在进行同样的过程 This same process still happens in our sun which is
它提供着我们赖以生存的能量 where we get the energy we need to live.
但我们今天的一切 But there was still a long way to
是历史长河中久经锤炼而来 go to get from this to where we are today.
仅用氢气和氦气这样的气体 You can't build a world like ours
无法构建出我们这样丰富多彩的世界 from simple gasses such as hydrogen and helium.
其他各种元素必不可少 You need all sorts of other elements.
比如氧 碳 铁等元素 You need elements like oxygen and carbon and iron and many more.
幸运又一次降临 But, we got lucky yet again,
因为导致恒星发光的过程 beacuse the very same process that causes the stars to shine
正巧产生了氧气 碳 铁等物质 also just happens to make materials like oxygen and carbon and iron.
意外形成恒星相当于大型化学工厂 Stars simply by accident are giant factories.
观测一颗活跃的恒星 To see a star in action,
让我们设想可将其分成两半 let's imagine I can split one in half.
如那颗足球大的恒星 Just as in the soccer ball star,
氢聚合成氦 the hydrogen atoms are fusing together, creating helium,
产生了恒星释放的能量 which produces the star's energy.
然而氦比氢略重 But helium is slightly heavier than hydrogen,
因此会下沉到恒星中心 so it sinks to the center of the star.
现在氦原子占据中心位置 And now the helium atoms take center stage.
更多能量伴随它们的聚合而产生 As they fuse together, they produce even more energy,
形成另一种新元素 and form yet another new element,
碳 carbon,
所有生命必不可少的组成部分 a vital building block of every living thing.
该过程循环往复 The process repeats itself over and over
星体开始分层 像洋葱一样 and the star becomes layered, like an onion,
像巨大的洋葱 a really big onion.
距离中心越近 元素质量越重 The closer to the center, the heavier the elements,
比如氖 氧 最后是铁 like neon, oxygen, and last of all iron.
现在事情发生了变化 Now things change.
铁在聚合时不产生能量 因此燃烧开始停止 Iron doesn't produce energy when it fuses, so the fire begins to go out.
越来越多的铁集聚于恒星内核 More and more iron builds up in the star's core
直至剩余燃料耗尽 until almost all the remaining fuel runs out.
接着万有引力开始作用 挤压恒星自身 Now gravity takes over and squashes the star in on itself.
随着恒星的内核越来越紧密 As its core gets more and more compressed,
其温度涨至超过太阳内核一百余倍 its temperature soars until it's over 100 times hotter than the core of our own sun.
最终恒星塌陷并发生爆炸 Finally the star collapses and explodes.
这就是超新星爆炸 This is a supernova.
一颗恒星的灭亡 The death of a star.
伴随着新事物的诞生 And the birth of something new.
在这短暂的数微秒中 In these brief microseconds,
一个巨大的冲击波掠过恒星 a massive shock wave passes through the star.
威力强大的冲击波迫使一些铁元素 The blast is so powerful that it forces some of the iron
聚合成更重的元素 to fuse into even heavier elements.
这就是重元素 And that's how heavy elements
诸如金 铂 铅等产生的过程 such as gold or platinum or lead are made,
它们产生于爆炸中的恒星内核 forged in the heart of an exploding star.
如果你有一枚金戒指 So if you have a gold ring,
一定要珍惜它 make sure you appreciate it.
这种金属诞生于 The metal was made in a
数十亿年前的一道刺眼强光 blinding flash of light billions of years ago.
这一过程的结果是 The finale of the process
产生了今天我们周围的所有元素 that produced the elements all around us today.
我一直感到惊叹 It never ceases to amaze me
我们的身体是由恒星里的物质构成 that our bodies are constructed of the stuff of stars,
我们的心跳 that our hearts beat
则归功于这些物质生成时所产生的能量 because of the energy given off as those materials are made.
然而 除了恒星的神奇 But as magical as a star is,
浩渺的宇宙蕴藏着更加迷人 强大的东西 there are the more fascinating and powerful things in our enormous cosmos.
大约宇宙大爆炸的三亿年后 Around 300 million years after the Big Bang,
早期星体开始逐步形成 the early stars began to form galaxies
令人炫目的形状和大小多样的星系 which slowly took on a bewildering variety of shapes and sizes.
我们的星系 银河系 Our galaxy, the Milky Way,
被认为是最古老的星系之一 is thought to be one of the oldest,
早在约130亿年前就开始聚集 having started to assemble itself some 13 billion years ago.
其直径约为六万亿英里 It's roughly 6,000 billion miles in diameter
包含约2千亿颗独立恒星 and contains something like 200 billion individual stars.
没有人知道确切数目 Nobody is quite sure exactly how many
因为从地球上无法尽收眼底 since they can't all be seen from Earth and anyway,
再说去数它们要花很长时间 it would take a long time to count them.
由于所有的恒星都因万有引力而产生 Because all these stars were built by gravity,
可以说 万有引力是宇宙的英雄 you could say that gravity is the hero of the universe.
毕竟 它将一缕缕无意义的气体 After all, it turned a meaningless soup of gas
化作集美丽和力量于一体的恒星 into something of beauty and power.
就像所有鲜活的英雄形象 But like all interesting heroes,
万有引力也有它黑暗的一面 gravity has its dark side.
在我们星系的正中心有个例子 Right in the center of our galaxy lies an example of
证明万有引力占据统治地位时 会发生什么 what happens when gravity rules unchallenged.
黑洞 A black hole.
我二十多岁时 When I was in my 20s,
对黑洞进行过一些基础演算 I did some of the basic mathematics of black holes,
但少有人与我志同道合 but few people shared my fascination.
现今 黑洞成为流行的课题 These days, they are a popular subject.
全世界的物理学家都在研究黑洞行为 Physicists all over the world are studying black hole behavior.
现在我们知道黑洞 We now know that black holes
不仅因它们自身的特点受到欢迎 are not only fascinating in their own right,
还因为它们在星系形成过程中 but that they play a
起到至关重要的作用 fundamental role in the formation of galaxies.
同时让我们得以一窥宇宙可能的灭亡方式 They also give us a glimpse of how the universe may end.
当一颗比太阳大20倍的大恒星 A black hole forms when a large star,
走向生命尽头时 黑洞就产生了 one say, 20 times the mass of our sun, comes to the end of its life.
这样的恒星与太阳完全不同 Such a star looks nothing like our sun
因为开始灭亡时 because it's become unstable,
它变得不稳定并剧烈震动 convulsing violently as its death throws begin.
最终 它燃料耗尽 开始收缩 Finally it runs out of fuel and begins to shrink,
密度越来越大 温度越来越高 getting denser and denser, hotter and hotter.
但对于如此巨大的恒星 But with a star this massive,
宇宙中没有任何力量 there is no force in the universe
能够阻止恒星崩塌 capable of stopping the collapse.
内核太过沉重以至于不断坍缩 The core is so heavy that it just keeps on falling in on itself.
万有引力如脱缰之马 Gravity is running wild.
仅仅十五秒钟左右 In just 15 seconds or so,
这股无坚不摧的力量将此恒星直径 the unstoppable force crushes the star from
从数百万英里压至十二英里 millions of miles in diameter to as little as 12 miles in diameter.
恒星的质量没有发生改变 All the mass that was in the star is still there,
但它自身的重量 but its own weight keeps
一直在迫使它变得越来越小 forcing it down smaller and smaller still.
内核温度飙升至一千亿摄氏度 The temperature of the core sores to 100 billion degrees.
恒星外层在剧烈的超新星爆炸中解体 The outer layers are blasted away in a massive supernova.
但在恒星中心深处 内核逐渐陷入 But deep in the center, the core falls down
所谓的重力势阱 what we call a gravitational well.
它坍缩成一个点 It crushes itself into a single point.
黑洞便诞生了 A black hole is born.
附近的一切都无法逃脱它的引力 Nothing nearby can escape its pull,
甚至光也难以幸免 not even light.
黑洞的密度大到人类难以想象 It's hard to imagine just how dense a black hole can be.
但我要借用大家熟悉的事物进行深入剖析 But I'll try to put it into perspective using something familiar.
地球 The Earth.
想象将地球分成一片一片地进行压缩 Imagine, piece by piece, I could compress our planet
在万有地心引力接手前一直对其挤压 and crush it until gravity took over.
于是它变成黑洞 And it became a black hole.
它要达到多小才能 How small would it have to
陷入自身的重力势阱呢 be to vanish down its own gravitational well?
我需要将它从直径八千英里压至一粒豌豆大小 From 8,000 miles in diameter, I'd have to crush it to the size of a pea.
我研究黑洞的这些年里 In my years studying black holes,
一个发现非常出乎意料 one of my most unexpected discoveries was
即黑洞不完全是黑色的 that a black hole cannot be perfectly black.
如同早期宇宙 For much the same reason as the early universe
不能完美无缺的分散一样 could not have been perfectly spread out,
世间不存在十全十美 there is no such thing as perfection.
黑洞一定会释放辐射 Black holes must give off radiation.
黑洞越小 辐射越强 The smaller the black hole, the greater the radiation.
甚至轻至山体质量大小的微型黑洞也会发光 and even a tinier black hole with only the mass of the mountain range would actually shine.
太空中 多数黑洞都较大 Out in space, most black holes are much larger.
小黑洞约是太阳质量的四倍 The smaller ones have around four times the mass of our sun.
直径约十五英里 and are 15 miles in diameter.
有些非常大 Some are much larger,
相当于数千个太阳的质量 containing the mass of thousands of suns.
还有一些相当大的黑洞 And then there are the really big ones:
特大质量黑洞 supermassive black holes,
它们存在于银河系似的星系中心 that exist at the centers of galaxies like our own.
这个黑洞质量相当于四百万个太阳 This black hole is thought to have the mass of four million suns,
直径一千一百万英里 and a diameter of 11 million miles.
这样的黑洞是像银河系等 Black holes like these are the heavy hubs around
众多星系围绕的巨大中心 which many galaxies including the Milky Way rotate,
也是维持它们形态和轮廓的稳定器 a kind of stabilizer that gives them form and shape.
宇宙大爆炸八十亿年后 So eight billion years after the Big Bang,
携着长时间显著的好运气 after a long and remarkable run of good luck,
宇宙中出现了在围绕巨大黑洞 we have stars and we have galaxies,
缓慢旋转的星体和星系 slowly rotating around giant black holes.
我们所熟悉的事物即将依次出现 Now the scene is set for something close to our hearts,
太阳 地球的形成 the formation of our sun, the Earth,
最终 我们人类 and ultimately us.
太阳系 我们的家园 Our solar system, the place we call home
位于距离银河系中心二万六千光年的地方 lies about 26,000 light years from the center of our galaxy, the Milky Way.
或说是银河系直径的三分之二处 or around two thirds the way out.
这些巨大行星用了六百万年才开始 The story of how these huge planets came to be orbiting
环绕一颗中等大小的金色恒星运行 an average yellow star is six billion years long,
由于时间有限 我会加快速度解释过程 and since we don't have that much time, I'll speed it up a bit.
故事的开头是一个大爆炸 It starts with a bang.
很久以前 一颗古老的恒星发生爆炸 Long ago an ancient star exploded,
向空中抛出旋转的它燃烧时产生的物质云团 littering space with swirling clouds of the materials it had made while it lived
和灭亡时产生的更重的金属 and the heavier metals it created as it died.
我们之所以知道这些是因为 We know this because we
现今能从星际尘埃中看到相似的感觉 can see similar feels of dust out in space today.
它们叫作星云 形态绚丽多彩 They are called nebulae and they are very beautiful.
每个星云都不同 Every nebula is different,
我们的星云包含氮 氧 铁 硅 and in our case the clouds contained nitrogen and oxygen and iron and silicon
和其他构成丰富多彩的世界所需的东西 and all the other stuff needed to build a world like ours.
接着 不知疲倦的万有引力开始 Then the tireless force of
将一切牵引到一起 gravity started to pull it all back together.
创造行星的浩大工程开始了 And the heavy engineering that produces planets began.
大量尘埃飞扬 开始排列 Vast spirals of dust began to form
某片尘埃中央 and at the center of one of these,
一颗称为地球的岩状行星开始成形 a rocky planet called Earth started to take shape,
由星尘为材料 由万有引力组建而成 built of stardust and assembled by gravity.
快速掠到一亿年后 Fast forward 100 million years
它成长为一个巨大的球体 and it had grown into a giant ball,
横扫数十亿吨太空碎片 sweeping up billions of tons of celestial debris.
这就是地球的起源 This is where the Earth came from,
也是你我的起源 and, therefore, how you and I began.
不过地球将永远是个 But our planet would have remained
布满岩石 金属 矿物质的贫瘠星球 a large sterile ball of rock and metals, minerals forever,
如若没有一项其他因素 were it not for one more event,
一项自然发挥的神奇力量 one more expression of the forces of nature.
九千三百万英里以外的巨大云团中心 93 million miles away at the heart of the giant nebula,
氢气团的压力和温度巨大 the pressure and temperature of a ball of hydrogen gas had become so great
原子开始聚合 that the atoms were beginning to fuse.
一颗新的恒星 太阳 诞生了 A new star, our sun, was coming to life.
太阳发光 释放出强大的太阳风 As the sun ignited, it gave off a huge blast of solar wind,
这是一种有辐射的能量风 a radioactive gust of energy.
太阳风将星云残余尘埃和气体 This blew all the remaining dust and gas that was left over from the nebula
吹到太阳系边缘 out to the edge of the solar system
这也是如今一切都井然有序的原因 which is why everything is nice and orderly today.
在太阳系里的外部区域 In the outer reaches of the solar system,
有巨大气体行星:木星 土星 天王星 海王星 we have the huge gas planets, Jupiter, Saturn, Uranus and Neptune.
更近一些是密度更大 岩石更多的行星: Further in are the denser, rockier planets,
水星 金星 火星 当然还有地球 Mercury, Venus, Mars, and of course the Earth.
幸运的是 太阳直径八十万五千英里 Lucky for us the sun is 865,000 miles in diameter
尺寸正巧足以长时间持续燃烧 or just the right size to burn consistently for a very long time.
八十亿年 Eight billion years.
时间足够让接下来的演化发生 Long enough to allow the next development to take place.
生命 Life.
生命是现知的最奇特的现象 Life is one of the strangest phenomena known.
在我看来 它表明宇宙无所不能发生 In my opinion, it shows that the universe is capable of almost anything.
我始终惊叹 人类竟能了解如此多 Yet it amazes me that we can know so much about
数十亿年前宇宙如何起源的 how the universe began many billions of years ago,
不过我们还没发现生命的起源 but we have yet to discover how life itself began.
最可能的解释就是 也许我们的存在 The most likely explanation is probably that we are
只是一次意外 an accident.
机缘巧合下 一些分子随机地进入其他分子 Just by chance, some molecules bumped into each other at random
直到最后组合了一个可以自我复制的个体 until finally one formed that could copy itself.
接着 缓慢的进化过程开始了 Then began the slow process of evolution
这形成了地球上生命的多样性 that led to all the extraordinary diversity of life on Earth.
只要有适宜的环境 Life seems to be simply
和充足的时间 物质似乎就能构成生命 what matter does given the right conditions and enough time.
我认为生命遍及整个宇宙 I think that life is probably quite common throughout the universe,
不过那是另外一个故事了 but that's another tale all together.
生命在演替的同时 也改变着孕育它的星球 As life developed, it changed the planet on which it was born,
改变着地球特有的构造 altering the very fabric of the Earth.
45亿年后 人类登场了 After four and a half billion years, the human race arrived on the scene.
但人们听这故事时 常常被一个问题困扰 But one thing often troubles people when they hear this story.
一系列导致我们出现的事件 How could such an astounding chain of events
怎会仅出于偶然 which resulted in us be an accident?
或许科学已经揭示还有更高等的权威在运作 Perhaps science has revealed there is some higher authority at work,
制定自然法则 使宇宙和我们得以存在 setting the laws of nature so that our universe and we can exist.
乍看起来 On the face of it,
生命的出现不太可能是巧合 life does seem to be too unlikely to be just a coincidence.
仔细想想 Think about it.
地球恰好与太阳距离适当 The Earth lies at exactly the right distance
使地表能够存在液态水 from the sun to allow liquid water to exist on its surface.
而太阳也恰好大小适中 And the sun just happens to be the right size
足以燃烧数十亿年 足够生命得以进化 to burn for billions of years long enough for life to have evolved.
太阳系中充满生命所需的所有元素 The solar system is littered with all the elements needed for life.
只有古老恒星消亡 These elements themselves are only possible
这些元素才能产生 because of older stars that have burned out.
而只因为早期原始气团的微不均匀 These older stars only existed
这些古老恒星才能存在 because of a tiny unevenness in the early primordial gas,
它自身源于大爆炸产生的粒子海洋中 that was itself produced by a one in a billion imbalance
十亿分之一的不平衡 in the sea of particles that came from the Big Bang.
真能有一位伟大的设计师 So is there a grand designer
让这一系列小概率事件一一实现吗 who lined up all this good fortune?
在我看来 未必 In my opinion, not necessarily.
这样来看吧 Look at it this way.
如果还存在其他宇宙呢 What if there were other universes?
一些不及我们宇宙幸运的宇宙 Ones not as lucky as ours.
每一个宇宙都源自各自的大爆炸 Each of these universes could have come from its own big bang with
拥有各不相同的物理定律和环境 different laws of physics and different conditions.
一些也许并不存在重力 更谈不上出现生命 In some, gravity might not exist and there could be no life.
另一些氢气则没有发生聚合反应 In others, hydrogen might not fuse, so there
使得那里没有恒星 也没有生命 would be no stars and again no life.
出于各种原因 For any number of reasons,
宇宙也可能由产生到消亡根本没产生任何物质 universes could have come and gone without producing anything at all.
因此 也许我们不必过于惊讶 So perhaps we should not be too surprised to
发现我们生于一个完美的宇宙 find ourselves in a perfect universe
在一颗围绕完美太阳旋转的完美星球上 orbiting a perfect sun on a perfect planet
因为只有这般完美的星球 because such perfect places are the only ones
才适宜我们这样的生命存在 where life like us can exist.
我们是宇宙的众多产物之一 We are one of the many products of the universe,
古老且精妙的演进过程的结晶 the result of an ancient and elegant mechanism,
然而 即便是如此非凡的发现 but even this remarkable discovery is
也只是物理学所能告诉我们的皮毛 only just the beginning of what physics can tell us.
我们可以探明人类在久远未来将面临的危机 We can find out what human kind will face in the distant future.
并可能最终揭开宇宙自身命运之谜 And ultimately, we might discover the fate of the universe itself.
我喜欢宇宙学的原因之一是 One reason I love cosmology is that
它不仅告诉我们 it tells us not only
宇宙中巨大的星系网从何而来 where the vast web of galaxies in our universe came from,
还透露宇宙及我们未来可能发生的事 but also what lies in store for both the universe and for us.
能成为首批看到往后数百年 数十亿年 I think it's pretty exciting to be among the first human beings
甚至时间终结之时景象的人 able to look forward for hundreds and even billions of years,
是件激动人心的事 maybe as far as the end of time itself.
我看到的不仅是我们所栖息的宇宙的未来 What I see is not only the future of the cosmos we inhabit,
还有人类所要面对的巨大挑战 but also the enormous challenges our species will face.
毕竟 相对于创造出我们的宇宙来说 After all, we are puny organisms compared
我们是微不足道的 to the mighty universe that made us.
甚至连赋予我们生命的地球 Even the Earth that gave us life
也不可能永远充当我们蔚蓝的避难所 will not always be the blue sanctuary that is today.
地球上的大陆正在漂移 The continents of our planet are drifting.
快进七千五百万年 Fast forward 75 million years and they
它们将朝着南极聚拢 will be clustered towards the south pole.
没人知道地球将来还是否适合居住 No one knows if the Earth will still be habitable then,
但遗憾的是 but the sad truth is that
人类也许活不到见证的一刻的出现 we may not last long enough to find out.
我们凝视未来时 As we gaze into the future,
会发现其实宇宙颇为危险 it turns out that the universe is a pretty dangerous place.
看看地球周边即可略知一二 Just look at our neighborhood.
这里存在着数十亿颗小行星 It's littered with billions of asteroids,
都是太阳系形成时期存留下来的古老的残骸 ancient remnants left over from the process that built the solar system.
它们毁灭我们的可能性 The possibility of one of these wiping us out
并不只停留在好莱坞虚构的灾难片中 isn't just the stuff of Hollywood disaster movies.
小行星的威胁是真实存在的 The threat from asteroids is real.
我们已经为其中一些命名 We've even given some of them names.
这一颗叫阿波菲斯 This one is called Apophis,
得名自埃及神话中的一个恶魔 after a mythical Egyptian demon,
黑暗与毁灭之神 a god of darkness and destruction.
于2004年被发现的阿波菲斯 Discovered in 2004,
大小相当于百层摩天大楼 Apophis is the size of a 100-story skyscraper.
重约二百亿吨 It weighs about 20 billion tons.
以每小时二万八千英里 子弹的十倍速度 Speeding through space at 28,000 miles an hour,
穿梭于宇宙之中 10 times as fast as a bullet,
它所具有的能量几乎是 it carries almost as much energy as
世界上所有核武器所具能量的总和 all the world's nuclear weapons combined.
我们目前只知道其大致走向 And we know roughly where it's headed.
其精确路径还有待研究 The precise path is not yet fully known.
但在2029年4月13日 But on April 13th, 2029,
这块巨石很可能在距地球表面 this huge rock is likely to pass
约两万三千公里的位置经过 within 23,000 miles of the planet's surface.
近得能在地球轨道卫星下空掠过 Close enough to pass beneath the satellites in orbit around Earth
从而使我们担惊受怕 and give us all a scare.
幸运的是 阿波菲斯撞上地球的可能微乎其微 Luckily there is very little chance that Apophis will actually hit us,
但人类面临的真正问题是 but the problem for humanity is
宇宙中总是有更大的石块 that in space there is always a bigger rock.
太空中有成千上万巨大的小行星 There are thousands of really large asteroids out here.
有些长达十余英里 大小堪比曼哈顿 Some are over 10 miles long. The size of Manhattan.
每一亿年左右 An asteroid this size
就会有一颗这般大小的小行星撞上地球 hits the Earth every 100 million years or so.
最近的一次撞击发生在六千五百万年前 The last one struck the Earth 65 million years ago,
很可能正是恐龙灭绝的原因 and probably was responsible for wiping out the dinosaurs.
我们不知道下一颗小行星会在何时袭来 We don't know when the next asteroid will strike,
不过如果它足够巨大 就可能毁灭地球 but if it was big enough it could sterilize our planet.
那将是地球上五十亿年生命长河的终结 That would be the end of the 5 billion year long story of life on Earth.
但即使我们幸免于这一自然灾难 but even if we avoid such a natural catastrophe,
我们也可能轻易毁灭于自己之手 we could all too easily end up destroying ourselves.
在最近的一万年里 In the last 10 thousand years,
人类在地球上占据统治地位 humans have come to dominate the planet.
我们非常成功 We are so successful,
以至于认为自己是进化史上最璀璨的成就 that it's tempting to think we are evolution's grand prize.
但我想我们对自身智慧的评价过高了 But I believe intelligence is probably overrated.
这对于一个物种的生存并不是一件好事 It's not necessarily a good thing for a species' survival.
细菌在缺乏智慧的情况下 Bacteria have managed without it
存在了超过三十亿年 for over three billion years.
对人类而言 智慧至少会带来技术发展 Intelligence, at least in our case, leads to technology.
而技术却有很多毁灭我们的途径 And there many ways technology could wipe us out.
最显而易见的就是核武器带来的威胁 The most obvious, of course, the threat from nuclear weapons.
虽说今后一年内发生核战争的几率很低 Even if the risk of a nuclear war happening in one year is miniscule,
只有百万分之一的可能 say only one in a million,
但如果将范围扩大至十万年 if we run those odds over 100,000 years,
几率将会大幅提高至十分之一 the chance of catastrophe falls to one in ten.
个人认为 这个几率也有些过于乐观了 Personally I worry that even this might be overoptimistic.
即使人类的智慧足以设计出这样的武器 Although we are clever enough to have designed such weapons,
但我不认为人类拥有足够的智慧不使用它们 I'm not sure we are clever enough not to use them.
随着时间延续到未来 As time marches relentlessly into the future,
宇宙还为我们准备了更多惊喜 the universe has other surprises in store.
宇宙中还有更为强大的东西 There are some powerful things out there.
有些无需我们推波助澜 就能轻易毁灭地球 Some of which could destroy the Earth without any help from us.
随着宇宙继续沿着古老的节奏发展 As the universe continues to dance to its ancient rhythm,
恒星将进入一个永不间断的循环 stars will come and go in a relentless cycle
而正因为有着上千亿颗恒星 and because there are hundreds of billions of stars,
总有一颗在超新星爆发中消亡 there is always one dying in the supernova somewhere.
比如在银河系中 In our galaxy for instance,
大约每50年就有一颗恒星消亡 a star dies every 50 years or so,
这对于宇宙来说只是短短的一瞬 which is but the briefest of moments to the universe.
如果你从长远的角度看 不难想象得到 It's just about conceivable that a supernova could damage the Earth,
超新星爆炸会对地球造成破坏 if you consider the likelihood over a long enough time scale.
一类偶然被发现的超新星爆炸 One kind of supernova discovered
是极具危险性的 entirely by accident is thought to be particularly dangerous.
1967年 冷战进入白热化阶段时 In 1967, when the cold war was at it hight,
美国军事卫星探测到 US military satellites picked up
一组名为伽马射线的大爆发 a massive burst of something called gamma radiation.
伽马射线是已知辐射中最危险的 Gamma radiation is the most dangerous type of radiation known.
这也能明显显示出使用核武器的迹象 It's also the tell tale sign of an atomic weapon
这组伽马射线能不能 whether the gamma rays detected
证明苏联具有新型大杀伤力炸弹呢 evidence of a new and powerful Soviet bomb,
还好答案是 不能 thankfully the answer was no.
经过仔细的数据分析 After careful analysis of the data,
他们发现伽马射线的突然爆发 they discovered that the sudden bursts of gamma rays
实际上来自太空 were actually coming from space.
即便是当时的俄罗斯也不可能具备这种技术 Not even the Russians had that kind of technology.
几十年后的今天 我们依然不知道 Decades later, we still don't have proof of
是什么产生了辐射的爆发 what causes the bursts of radiation.
但有一个被高度重视的理论 But there is a well-respected theory
说它们源自一种特别的超新星爆发 that they are produced by a special kind of supernova,
伽马射线暴 called a gamma ray burst.
而且有一个伽马射线暴可能存在于地球附近 What's more, there might be one quite nearby.
隐藏在巨大的漩涡状等离子群中 Hidden within this massive spiral plume of plasma,
距离地球八千光年的地方 8,000 light years from Earth
有一颗被称作WR 104的恒星 is a star called WR 104.
这颗恒星的内部深处是一个明亮的球体 Deep inside the star itself is a bright sphere,
在生命的尽头 它向外抛射出炙热的气体外壳 throwing off a shell of hot gas as it nears its end.
如果这恒星如我们所想 If this star is what we think it is,
就会在消亡过程中产生两束聚焦辐射束 as it dies it will produce two tightly focused beams of radiation,
两极各射出一束 one from each pole.
恒星在产生这两束辐射同时也在毁灭自己 The star destroys itself as it produces these beams
其中蕴含的能量 which contain more energy
比太阳一生所产生的能量还要多 than our sun will produce in its entire life.
这是已知的宇宙中最亮的现象 The brightest known phenomena in the entire universe.
没人知道WR 104是否会产生这现象 No one is sure if WR 104 will do this
也不知道这辐射束是否会射往地球 or if the beam would strike the Earth,
但要是这样 我们将沐浴于高强度的辐射中 but if so, we could be bathed in high intensity radiation
导致毁灭性的后果 with some devastating consequences.
辐射束将产生壮观的极光现象 The beam would cause spectacular auroras,
破坏大气层中的臭氧层 striking the ozone from the atmosphere,
让致命辐射从太阳直射地球 allowing deadly radiation from the sun to strike the Earth.
这听起来也许有些像科幻小说 It may sound like science fiction,
但这将是我们所能看到的第二次 but this could be the second time skies like these
像这样的天空 have been seen from our world.
四亿五千年前 450 million years ago,
过半生物在一次大灭绝中消失殆尽 over half of all living creatures were wiped out in a great extinction.
其中一个解释就是伽马射线暴辐射到地球 One explanation is that a gamma ray burster irradiated the planet so badly
导致地球的生态系统几乎崩溃 that Earth's ecosystem virtually collapsed.
我并不是想耸人听闻 I don't want to worry anyone,
但我认为 人类到外太空探险 but I think it's definitely a good idea
是个不错的主意 for the human race to venture far beyond the Earth.
我们应该把鸡蛋放到尽可能多的篮子里 We would be wise to keep our eggs in as many baskets as possible.
庆幸的是那个计划已经开始了 Thankfully that process has already begun.
在我看来 阿波罗11号的发射 In my opinion, the launch of Apollo 11
是人类历史上的一个重要时刻 is probably the most important moment in human history.
这也是宇宙的转折点 It was a turning part for the universe too.
我们这样的生命飞离母星 Life in the form of us escaped its home planet.
并站在了另一个星球上 And stepped on another surface.
宇航员的足迹一直保存至今 The astronauts footprints stand preserved to this day.
初步验证了我所认为的 A testament to the beginning of what I think
宇宙故事中的下一章: could be the next chapter in the story of the cosmos.
生命传播至宇宙其他地方 The spread of life to other part of the universe
随着宇宙的成长 我们也要变得更加智慧 As the universe gets older, we will have to get wiser.
我想我们应该探索比月球更远的地方 I think we will have to go much further than the moon.
起码也应该探索火星 At the very least to Mars.
这一红色星球很可能 The red planet is likely
在我们的进化过程中扮演着重要角色 to play an important part in our evolution.
甚至在宇宙发展历程中也是 and maybe even in the story of the cosmos.
它将是人类星际旅行的第二个 It's the second and possibly the most important steppingstone
很可能也是最重要的踏板 on humanity's journey to the stars.
机器人的火星探测任务展示了 Robot missions to Mars have revealed
一幅美丽而危险荒凉的壮观景象 a spectacularly beautiful yet dangerous and desolate place.
我想 人类拓荒者抵达这里一定很令人兴奋 I imagine that being a human pioneer here would be an exciting business.
首先 这里很寒冷 For a start, it's cold.
到太阳的距离比地球远五千万英里 It's 50 million miles further from the sun than the Earth
因此只接收到一半的热量 and so it receives half as much warmth
而且温度波动很大 and the temperatures fluctuate wildly.
数分钟内从80度降到零下200度 From 80 degrees to minus 200 in a matter of minutes.
如果寒冷的环境不能征服你 If the cold doesn't get you,
那么低重力一定能办到 the low gravity will.
火星只有地球的一半大小 Mars is just half the size of the Earth
而且重力只有地球的38% and has just 38% of its gravity.
久而久之 探索者的骨头将变脆 Overtime,explorers's bones would weaken
肌肉也将变得虚弱 and their muscles would waste away.
在火星上呆久了 Spent long enough on Mars,
你会发现自己太过虚弱而无法安全回到地球 and you could find yourself too weak to safely return to Earth.
低重力同时意味着火星很难形成大气 The low gravity also means Mars struggles to hold on to an atmosphere.
这里除了稀薄的二氧化碳以外 什么也没有 Here there is nothing more than a thin wisp of carbon dioxide
气压也只有我们气压的百分之一 at just one-hundredth the pressure of our air.
火星还沐浴在太阳的有害辐射中 Mars is also bathed in harmful radiation from the sun,
即使它离太阳更远 even though it's further away,
与地球不同的是 它没有磁场 unlike Earth it has no
也没有臭氧层的保护 magnetic field and no ozone layer to protect it.
早期探索者们 Early explorers would
必须小心让自己的暴露面积减到最小 have to be careful to minimize their exposure
或许他们还要居住在地下 and perhaps they would have to live underground.
但我认为 未来某天 But one day, I think it will be possible
我们很可能完全改变火星的生存条件 to drastically alter conditions on Mars,
比如利用空间反射镜供给热能与动能 perhaps using space-bourne mirrors to supply warmth and power.
在势必问世的更高科技出现后 With perfectly foreseeable technology,
更大的转变也将成为可能 much more could become possible.
若我们能够建造一个巨大的玻璃塑料拱顶 If we could erect giant domes made of glass and plastic
来阻挡辐射 to block out the radiation,
在拱顶之内 我们还能充实稀薄的大气 inside them we could enrich the atmosphere.
我相信 在未来短短500年之内 500 years from now which really is a very short time indeed,
火星人就会形成自己的语言 I think Mars will have its own language,
货币 甚至烹饪之道 its own currency, it's own cuisine.
不过我肯定你在那里仍旧能吃到汉堡包 Although I'll bet you will still be able to get a hamburger somewhere.
但随着宇宙的不断变老 But it's clear as the universe continues to age,
即使是这样的进展 even advances like these
也无法保证人类能够永久地繁衍生息 will not be enough to guarantee humanity's existence for a very long time.
在更远的未来 我们的太阳系最终 Look further into the future and ultimately our solar system
将与之前无数其他太阳系一样 will follow the same path as countless billions of solar systems before it
不复存在 and cease to exist.
现在的太阳正值壮年 Right now the sun is in the middle of its life cycle.
这一阶段 它将以每十亿年6%的速度 During this phase, it is getting gradually hotter
逐渐地变热 变亮 and brighter all the time by about 6% every billion years.
在约五十亿年后 In about five billion years,
太阳的温度将增至近两千亿度 the sun's temperature will have grown to nearly 200 billion degrees.
这时 At this point
地球将成为一颗难以辨认的熔岩球 the Earth will be an unrecognizable ball of molten rock.
地球上的生命也早已不复存在 All life having long since perished.
这是我们这个星球难逃的命运 This is our planet's unavoidable destiny.
但太阳将要带来的灾难远非如此 But that's not all the sun has in store.
当燃料消耗殆尽时 太阳便开始膨胀 As it runs out of fuel, the sun will start to expand,
变成红巨星 turning into what's called a red giant.
太阳因此从赐予生命的万物之母 It will change from being the object
变成了毁灭一切的灾星 that gaves us life to the one that annihilates it.
在约70亿年后 In about seven billion years,
太阳将膨胀为目前的200倍 the sun will be 200 times bigger,
直径将达2亿英里 about 200 million miles across.
巨大的太阳将逐个湮灭太阳系内层的行星 So vast it will obliterate the inner planets, one after the other.
水星 金星 Mercury, Venus,
大概还有生命早已绝迹的地球 and most probably the lifeless Earth.
但宇宙以自己的速度不断演进着 But as the universe continues to evolve at its own relentless pace,
如果它所孕育的生命能够幸存 new opportunities will present themselves to us
就一定有机会找到其他赖以生存的家园 if we are able to preserve the life that the cosmos made.
这是葛利斯581D This is Gliese 581D
它是已知最接近地球的巨大类地岩状行星 It's a large rocky, earth-like planet, the nearest known.
这颗 或类似的其他星球将有可能 It's just possible that this world or one like it could in the future
成为人类未来的新家园 become home to the human race.
第二个逃离太空无尽黑暗的避难所 A second sanctuary against the unforgiving blackness of space.
2007年人们发现了这颗大于地球7倍的星球 Discovered in 2007, it is seven times bigger than Earth.
它环绕着一颗比太阳小且红的恒星运行 It orbits a star smaller and redder than our own,
但它与该恒星的距离刚好 but lies at just the right distance from its sun
能够让其表面存有液态水 to allow water to exist on the surface.
但即使它是我们完美的第二家园 But even if this is the perfect home away from home,
仍有一个根本上的问题摆在眼前 there is a fundamental problem we will have to overcome.
葛利斯离我们非常 非常遥远 Gliese is a very, very long way away.
距地球二十多光年 More than 20 light years from Earth.
也就是120万亿英里 That's 120 trillion miles.
为让大家更直观地认识这段惊人的距离 To get some idea of this extraordinary distance
和它所意味着的挑战 and the challenge it presents,
想象一下 如果我们能搭上 I'm going to imagine that we could hitch a ride
现存最快的人造交通工具 on the fastest man-made object in existence.
旅行者一号 1977年发射 Voyager one was launched in 1977.
30多年后的今天 Now over 30 years old,
它航行的路程已逾130亿英里 it's traveled more than 13 billion miles.
它已完成了到木星与土星航行 It's mission so far has taken it to Jupiter and Saturn.
借用行星的重力作用加速 By using their gravity to boost speed,
这艘小型飞船已被载入了史册 the little spacecraft has entered the record books.
或许这样看起来不快 It might not look fast,
却在以每秒十一英里的速度于宇宙中穿梭 but Voyager is racing through space at 11 miles a second.
在地球上 秒速十一英里是这样的 On Earth, 11 miles a second looks like this.
时速三万九千英里 It's 39,000 miles an hour.
以此速度 我们每小时能绕地球一周半 At this speed, we could circle the globe one and a half times in an hour.
那么一艘速度达到旅行者号的飞船 How long would it take a spaceship
究竟要多久能抵达最近的类地行星葛利斯呢 traveling at Voyager's speed to get to the nearest earth-like planet, Gliese?
问题的答案让我们真正见识了宇宙之浩淼 The answer reveals the true scale of the cosmos.
即使秒速达到11英里 For even traveling at 11 miles a second,
到达葛利斯仍需三十五万年以上 the journey to Gliese would still take over 350,000 years.
我认为我们还是有机会 I think we have a chance to
成为这瞬息万变的宇宙中永恒的一部分 become a lasting part of the ever-changing universe
并去探索它的众多奥妙 and to discover what other wonders it might hold,
但为达到这一目的 我们必须在 but to do this, we will have to develop
科技发展上跨出一大步 new technology on an enormous scale.
而这将需开启巨大的工程 And that's going to take some serious engineering.
宇宙学领域有观点与我一致的众多专家 There are many in the field of cosmology who believe as I do,
认为找出一种在太空远距离航行的方法 that finding ways to travel great distances
是让人类在宇宙中幸存的关键 will be essential to keeping human life amazing in the universe.
如果我们能建造一台机器 If we could build a machine
在其他太阳系中穿梭 capable of traveling to other solar systems,
我们将开创一种美好的可能 we would open up a fascinating possibility.
即人类在数亿年后依然幸存 The survival of the human race for billions of years.
目前 工程师们 Present day engineers have
已开始苦心研究如何建造出这样的飞船 begun thinking about the principals of building such a ship.
它看上去可能是这样的 This is what it might look like.
它可能会用到核能 It could use atomic energy
或更高能的燃料 如反物质 or perhaps more exotic fuel such as antimatter
用其产生的巨大能量供给机器加速 supplying it with enormous amounts of power,
但我认为 真正的挑战并非科技 yet I think the main challenges won't be technical.
首要难题是资金 The first will be financial.
构建这样一艘宇宙飞船耗资巨大 The cost of constructing an interstellar spacecraft would be huge
而筹建它的社会几乎没有任何回报 and for the society that made it, there would be little pay back.
他们永不会再见到它 They would never see it again.
因此 建造这样一台机器 So constructing such a machine will
或成为人类历史上最无私的奉献 either be the greatest act of generosity in history
或只能留给探索者自己去筹资 or will have to be funded by the travelers themselves.
如此一来 第二个难题又来了 And that raises the second problem.
即使它能以让人头晕目眩的速度航行 Even if it could travel mind numbingly fast,
比如千倍于旅行者号 say 1,000 times faster than Voyager,
即秒速11000英里 11,000 miles a second,
这样到达最近的星系依然需要 a journey to the nearest star system would still take
73年 73 years.
如此长距离的航行意味着至少一代人 Such a long trip means that at least one whole generation of humans
需要在宇宙中度过他们的一生 would have to live their entire lives in space.
而我们还不能肯定 他们是否情愿 We couldn't exactly say they volunteered for the mission.
从伦理角度讲 把人送上这样一艘飞船 The ethics of sending a human cargo on such a voyage
必须经过周密的考虑 would have to be carefully considered.
除非我们能够延长人类的寿命 Unless we could extend human lifespans to long enough to
来完成这项重大的使命 make such massive journeys.
我想 这很可能是我们最后的解决途径 And that I think is what we will ultimately end up doing.
据我的个人经验 这一工程已经启动 The process has already begun as I know from personal experience.
我的肌肉已经萎缩 My muscles no longer function,
只有眼睛和大脑还能正常运作 although my eyes and my brain are still working pretty well.
但现代科技让我能够移动和与人交流 But technology helps me to move and communicate.
在未来 In the future,
科技将带给我们的远不止于此 technology will do much more than that for all of us.
未来的1000年内 Within the next 1,000 years,
我们将见证史无前例的身体能力的进化 we will see unprecedented changes in our physical capabilities.
基因工程将延长我们的寿命 Genetic engineering will give us longer lifespans
并提高我们的智商 and greater intelligence.
更改基因结构可以让我们的皮肤 Modifying our genes could give us skin
具备抵抗辐射的能力 that protects us from radiation,
能够在有毒的大气环境中呼吸 the ability to breathe poisonous atmospheres,
抵御感染侵袭 resistance to infection.
我们甚至可能利用人工合成的DNA We may even develop sophisticated artificial life force,
开发成熟的人工生命 using synthetic DNA,
设计并用以太空旅行 custom designed for the challenges of space travel.
这些蜕变能让我们顺利挺过长距离航行 These advances would allow us to survive long journeys
与恶劣的环境 and inhospitable worlds.
我想像着 当我们的后代 I imagine a time when our descendents
分散到银河系的各个星球上 spread to planets orbiting other stars all over our galaxy.
或许 更远一些 And perhaps further still,
载着各类生物探索尚未发现的太阳系 carrying their biological cargo to solar systems we have yet to discover.
这样设计下的飞船能够自由分离和散开 Ships like this one could be designed to split up and spread out.
一次真正意义上的生命迁移 A true diaspora of life
在人类的带领下展开了 that would have started with us.
随着我们穿梭于星际空间 As we journey across interstellar space,
我相信 我们将揭开自然深藏的秘密 I'm sure we will unlock nature's deepest secrets.
最大的成就将是发现宇宙如何终结 My greater is that we will discover how the universe will end
并揭开终极谜团: and solve the ultimate mystery:
即宇宙究竟为何会存在 why the universe ever existed at all.
我有一次在日本讲座时 I once gave a lecture in Japan
被告知不能提及宇宙终结的问题 where I was asked not to mention the end of the universe
以防引发日本股票下跌 in case it affected the Japanese stock market.
我不知道宇宙是否或何时会终结 I don't know if or when the universe will end,
但我想对为自己投资感到紧张的人说 but for those of you who are nervous about your investments,
我认为还是早一点抛出为好 I think it's a bit early to sell.
137亿岁 我们的宇宙仍旧年轻朝气 At 13.7 billion years old, our universe is still in its youth.
宇宙学家认为 宇宙的终结最早也要在 The earliest date we cosmologists think it could end
300亿年后 is 30 billion years from now.
但世事难料 There is still plenty of action to come.
即使我们的太阳消亡了 还有新的恒星形成 Even long after our sun has died, new stars will be borned,
它们中的一些也会有自己的行星 some of which will have new planets around them,
这些行星上也会由组成你我的原子组成 made of the same atoms that make you and me.
或许我们最终将变为外星生态系统的一部分 Maybe we will end up as part of some future alien ecosystem,
虽说这多少有些天方夜谭 although that's probably a bit of a long shot.
但不变的是我们不过是 What's true is that we are only the temporary custodians of
组成我们的这些微粒的暂时占有者 the particles of what which we are made of.
而它们将继续 They will go on to need a future
在浩瀚的宇宙中寻求未来的存在方式 existence in the enormous universe that made them.
当然万有引力仍会孜孜不倦地发挥作用 Certainly gravity will continue its tireless incessant work.
就像大爆炸后一样 It will go on shaping the vast strings of galaxies
继续改变着巨大银河网系的形状 as it has ever since the Big Bang.
利用超级计算机 Using super computers
我们可以模拟出万有引力是 we can simulate how gravity even now
如何使各星系相互吸引 并最终缓慢碰撞 causes galaxies to be attracted to one or another, resulting in vast slow collisions.
我们的银河系将在30亿年后 Our galaxy will emerge with its nearest neighbour
与近邻仙女座星系相撞 the the Andromeda Galaxy in aroud three billion years,
缓慢移动的碰撞将会持续二十亿年 a slow motion collision that will take place over two billion years.
宇宙中到处都在发生这样的碰撞过程 The same process is happening all over the cosmos.
所有的星系都在不断地发生碰撞和重建 Entire clusters of galaxies are constantly colliding and reforming.
数万亿恒星相互吸引而产生的巨大冲撞 Giant collisions as trillions of stars pull on one another,
所产生的大量碎块使得星系开始旋转起舞 their vast masses causing them to spin and dance.
万有引力仍然像在宇宙大爆炸开始时那样 Gravity is driving the cosmic clock work
驱动着宇宙时钟的运行 as it done ever since the big bang.
这就是当我们脱离人类尺度上的时间 This is what the universe looks like
所看到的宇宙面貌了 when we are released from time on a human scale.
但宇宙的这种旋转永远持续下去吗 But will this cosmic whirlpool go on forever
让能量与质量 时间与空间无尽地缓慢碰撞 as an endless mild storm of mass and energy, space and time?
能提出这样的问题是多么不简单啊 What an extraordinary question to even be able to ask.
我认为答案就在一切开始的地方 I think the solution lies back where we began,
宇宙大爆炸 with the big bang.
问问你自己 Ask yourself this.
是什么最先引起了宇宙的膨胀或是扩张 What caused the inflation or expansion of the universe in the first place?
等我们能够回答这个问题 When we can answer that
并完全理解宇宙大爆炸的时候 and fully understand the Big Bang,
我们也就能够知道宇宙的命运 we will also learn the fate of the universe.
宇宙命运的关键是一种叫做暗能量的物质 The key to it all is something called dark energy.
一种神秘形式的能量 A mysterious form of energy
它能够使空间本身相分离 that pushes space itself apart,
即便存在着能将物质聚在一起的万有引力 even as gravity is making matter clump together.
看上去似乎是暗能量使得宇宙得以膨胀 It seems as if dark energy supplied the kick that inflated the universe,
尽管我们并不知道究竟是如何做到的 although we are not quite sure how.
可以肯定的是 What is certain is
宇宙的命运依赖于暗物质如何进行反应 that the fate of the universe depends on how this dark energy behaves.
如果暗物质逐渐变弱 If the dark energy slowly weakens,
万有引力便会占据上风那么大约两百亿年之后 then gravity could get the upper hand
那么大约两百亿年之后 宇宙会开始倒转 and in 20 billion years or so, the universe goes into reverse
将一切都拉回到宇宙的起源 and drive everything back to where it came.
在宇宙大爆炸的奇异倒转之中 In a strange reversal of the Big Bang,
空间会进行收缩 space itself would contract.
这个理论叫做宇宙大挤压理论 This theory is known as the Big Crunch.
如果理论是正确的 那么最后 In the end, if the theory is right,
在距今三百万年之后的未来 in 30 billion years from now,
宇宙中的所有物质都会被一个黑洞所吞没 all the matter of the universe would be swallowed by a single black hole.
整个宇宙将会变成一个小点 The entire universe would exist as one tiny point,
和宇宙大爆炸发生时的大小差不多 much as it was at the instant of the Big Bang.
尽管这是个有道理的结局 But although that's a neat ending,
我却认为更加有可能的是 I think that it's more likely
暗能量能使宇宙永远膨胀下去 that dark energy will drive the expansion of the universe forever.
最终一切都会继续扩散 And ultimately everything will just keep spreading out
直到宇宙变得冷却与黑暗为止 until the universe is cold and dark.
一切都会相距甚远 Everything will become so far apart
以至万有引力也将不再起作用 that even gravity will be defeated.
宇宙冷却才是我们会遇到的结果 I think a big chill is what we have got in store,
而不是宇宙大挤压 not a big crunch.
这就是我们与所有生命的终结吗 So will this be the end of us and life as we know it?
或是在那之前 Or will we have figured out
我们已经具备远航至其他宇宙的能力呢 how to navigate through a new universe before then?
我想只有在我们完全了解宇宙起源后 I think we will only know when we truly understand
才会知道问题的答案 why the universe exists at all.
或许当我们最终揭开宇宙谜题时 Perhaps then when we finally unravel the whole cosmic puzzle,
我们就会成为主宰 we will become masters,
不仅主宰我们的宇宙 not just of the universe,
也将主宰其他宇宙 but the universe next door.