我们为何在此 Why are we here?
我们又来自何方 Where do we come from?
这些问题源远流长 These are the most enduring of questions,
而人类天性就爱探索答案 and it's an essential part of human nature to want to find the answers.
追根溯源 And we can trace our ancestry back
时间定格在几十万年前 人类文明出现之刻 hundreds of thousands of years, to the dawn of humankind,
实际上 我们的故事将延伸至更早的年代 but in reality, our story extends far further back in time.
从宇宙起源说起 Our story starts with the beginning of the universe.
宇宙起源于一百三十七亿年前 It began 13.7 billion years ago.
而今 宇宙中已形成逾千亿星系 And today, it's filled with over 100 billion galaxies,
每个星系包含数千亿恒星 each containing hundreds of billions of stars.
在这个系列里 我想向大家讲述这故事 In this series, I want to tell that story because,
因为说到底我们也是宇宙的一部分 ultimately, we are part of the universe.
宇宙的故事 便是我们的故事 So its story is our story.
这个故事的主角便是引力 The force at the heart of this story is gravity.
这最基本的自然力量建立了我们见到的一切 This fundamental force of nature built everything we see.
它创造了形状和秩序 It creates shape and order,
它的鬼斧神工在宇宙中比比皆是 and it initiates patterns that repeat across the heavens.
但引力也在宇宙中 But gravity also forges
打造了另一些截然不同的世界 some of the most alien worlds in the cosmos,
与信念相悖的世界 worlds that defy belief.
在探寻这基本自然力的真谛的途中 The quest to understand this fundamental force of nature
促生了一个创新 探索 发现的黄金年代 has unleashed a golden age of creativity, exploration and discovery.
这让对于身处宇宙中的我们 And it's led to a far deeper understanding
对此有了更深远的理解 of our place in the universe.
宇宙的奇迹
陷落
我们生命中的每一刻 Every moment of our lives,
都在体验一种我们看不见摸不着的力量 we experience a force that we can't see or touch.
然而这种力量能使我们扎根与地面 Yet this force is able to keep us firmly rooted to the ground.
它 就是地心引力 It is, of course, gravity.
尽管它难以名状 But despite its intangible nature,
它却一直如影随形 we always know it's with us.
如果我问你 If I was to ask you,
你怎么知道周围有地心引力 "How do you know that there's gravity around here?"
你也许会说 这很明显啊 Then you might say, "Well, it's obvious."
我可以做个实验 扔点什么东西 You know, I can just do an experiment, I can drop something.
没错 但实际上 Well, yes, but actually,
地心引力比这更令人难以琢磨 gravity is a little bit more subtle than that.
但为了真正体验它 理解它 But to really experience it, to understand it,
你必须使出点绝招来 you have to do something pretty extreme.
为此 我们改装了这架飞机 And this plane has been modified to help me do it.
根据飞行计划 它被形象地称为喷发彗星 Thanks to its flight plan, it's known as the Vomit Comet.
攀升至一万五千米的高空之后 Once we've climbed to 15,000 metres,
这架飞机将进行一些非比寻常的动作 this plane does something no ordinary flight would do.
关小油门的喷气式飞机将直落向地面 Its engines are throttled back, and the jet falls to earth.
然后 神奇的事情发生了 And then, something quite amazing happens.
推我一把 推我一把 Push to me, push to me!
我正垂直落向地面 I'm now plummeting towards the ground
就像有人切断了电梯里的缆绳 just like someone's cut the cable in a lift,
你瞧 我没有掉下去 and you see that I'm not moving.
就像爱因斯坦说的 我们只是浮在空中 Relative to Einstein, we're all just floating.
我们仅仅是同飞机以相同的速度下落 By simply falling at the same rate as the plane,
便能在某些瞬间 逃离地心引力的掌心 for a few fleeting moments, we are all free of gravity's grip.
但这可不仅仅是一番玩乐 But this isn't just a joyride.
这里有些意义深远的东西 There's something very profound here,
因为尽管如你所见 我正落向地面 because although I'm falling towards the ground, as you can see,
地心引力已经完全消失了 gravity has completely gone away.
地心引力在这里不存在了 Gravity is not here any more.
仅仅通过下落 我就挣脱了引力的束缚 I've cancelled gravity out just by falling.
如果你能理解这一点 你便能理解引力 If you understand that, then you'll understand gravity.
所以 通过这种简单的落体运动 So it is possible, by the simple act of falling,
我们便能获得一番截然不同的引力体验 to get a very different experience of gravity.
但是这种自然之力 But this force of nature does more
可不仅仅是将我们引回地面这么简单 than just bring us back down to earth.
引力也在方方面面扮演着重要角色 Gravity also plays a role on the grandest of stages,
因为纵观整个宇宙 because across the universe,
从极其微小的微粒 到质量巨大的恒星 from the smallest mote of dust to the most massive star,
无一不出自引力的巧夺天工 gravity is the great sculptor
它在混沌中创造出了秩序 that created order out of chaos.
自从有时间开始 Since the beginning of time,
引力就进驻了我们的宇宙 gravity has been at work in our universe.
以原始气团和宇宙尘埃为材 From the primordial cloud of gas and cosmic dust,
引力锻造了恒星 gravity forged the stars.
它又造出行星和卫星 It sculpted the planets and moons,
并将它们放置在新兴恒星周围的轨道上 and set them in orbit around the newly formed suns.
引力在庞大的星系中 And gravity connects these
把这些恒星系统联系到一起 star systems together in vast galaxies,
引导它们穿越这无垠的空间 and steers them on their journey through unbounded space.
经过数个世纪 Over the centuries,
我们努力理解引力 our quest to understand gravity has allowed us
这让我们能够解释宇宙中一些真正的奇迹 to explain some of the true wonders of the universe.
但是在更深的层次上 But at a deeper level,
也使我们提出 that quest has also allowed us to ask questions
关于宇宙自身起源和演变的问题 about the origin and evolution of the universe itself.
为了理解引力在宇宙中是如何作用的 To understand how gravity works across the universe,
我们不必看远 只需审视脚下 we need look no further than the ground beneath our feet.
第一位真正思考这问题的科学家 Well, the first scientist to really think about it
是1680年代的艾萨克·牛顿 was Isaac Newton back in the 1680s,
他是这么说的 and he said this -
万物之间皆有引力 "Gravity is a force of attraction between all objects".
很明显 这两块岩石之间的引力 Now, the force of attraction between these two rocks
十分微弱 几乎无法测量 is obviously very small, almost impossible to measure,
那是因为这种力 and that's because the force
是和物体的质量成比例的 is proportional to the masses of the objects.
这些石头还不够重 These things are not very massive.
但这附近有一块大得多的岩石 But there is a more massive rock around here.
它就是我现在站的地方 也就是地球 It's the one I'm standing on, planet Earth.
地球的质量使它能产生地心引力 The mass of our earth generates a gravitational pull
引力十分强烈 足以改变整颗行星的面貌 strong enough to sculpt the entire surface of the planet.
它引导水流开凿出大峡谷 It causes water to gouge out vast canyons.
它限定了山脉能耸多高 It sets the limit for how high mountains can soar,
它塑造了整个大陆 and it shapes whole continents.
但这看不见的力量不仅塑造了我们的世界 But this invisible force does more than just shape our world.
咱们头上的苍穹变幻莫测 The skies are always changing,
夜晚的星空周而复始地上演着 and the constellations rise and fall
斗转星移的剧情 in different places every night,
行星在以恒星为中心搭建的舞台上肆意徜徉 and the planets wander across the background of the fixed stars.
但纵观整个人类历史 But throughout human history,
夜空中总悬着一个熟悉的面孔 there's been one constant up there in the night sky,
因为每个过来人 都曾抬头凝视那弯明月 because every human that's ever lived has gazed up at the moon
亲历她那张光亮夺目的脸庞 and seen one face shining back at us.
我们之所以从未目睹月球的暗面 The reason why we never see the dark side of the moon
全源自引力使的小把戏 is all down to the subtlety with which gravity operates.
百万年前 月球飞快地自转 Millions of years ago, the moon rotated rapidly.
但是从它诞生的那一刻起 But from the moment it was born,
我们的卫星就受制于了引力 our companion felt the tug of gravity.
正如同月球让海洋潮起潮落 Just as the moon creates great tides in our oceans,
地球也在整个月球表面 the Earth caused a vast
引发了一次巨大的潮汐 tide to sweep across the surface of the moon.
但不同于潮水 But this tide wasn't in water.
它是由岩石组成的 It was in rock.
假如这是月球 那里是地球 Imagine that this is the moon, and over there is the Earth.
地球的引力作用于月球 The Earth's gravity acts on the moon and
将它拉扯成橄榄球的形状 stretches it out into a kind of rugby ball shape.
相对于地球来说 Now, the size of that tidal bulge
这股石头浪潮的高度大约有7米 facing the Earth is something like seven metres in rock
随着月球的自转 and then, as the moon rotates,
这股岩潮横扫月球表面 that bulge sweeps across the lunar surface.
想像一下这会是什么一种样子 I mean, imagine what that would look like here.
你会看见一波潮汐 You'd see a tidal wave sweep
席卷这片地区 across this landscape,
七米高的石浪升起又落下 with the rock rising and falling by seven metres.
这声势浩大的潮汐就像制动装置 This massive wave acted like a brake,
逐步减慢月球的自转速度 and gradually slowed the moon down.
最后 潮汐的步调终于与地球达到了一致 Eventually, the tidal bulge became aligned with the Earth,
锁定了月球旋转的速度 locking the speed of the moon's rotation.
所以月球旋转一周所需的时间 So the time it takes the moon to spin once
几乎跟它绕地球一周的时间一样 is almost the same as the time it takes to orbit the Earth.
所以月球没有暗面 So there is no dark side of the moon,
只是引力将月亮的那面藏了起来 just a side that gravity hides from our view.
地球和月球之间由引力而产生的联系 The bond that gravity creates between the Earth and the moon
也在整个宇宙中反复出现 is repeated across the cosmos.
它是将行星固定于环恒星轨道上的粘合剂 It's the glue that holds the planets in orbit around the sun.
它将我们的太阳系 And it binds our solar system
和无数其它太阳系联系到一起 and countless other solar systems together,
形成了如同我们银河系一般的星系 to form galaxies like our own Milky Way.
但引力的影响远不止这些 But gravity's influence can be felt even further
因为它掌控着星系的命运 because it controls the fate of galaxies.
当你仰望夜空 When you look up into the night sky
映入眼帘的是人们肉眼所见的那个宇宙 and you see the universe as it looks in visible light,
发光的恒星和星系 with the glowing of the stars and the galaxies,
但那只是故事的一部分 but that's only part of the story,
因为宇宙充满了尘埃和气体 because the universe is full of dust and gas
这些都是你无法用普通望远镜看到的 which you can't see with a conventional telescope,
但你可以用这种望远镜看到 but you can see with a telescope like this.
射电望远镜 比如新墨西哥州的甚大阵 Radio telescopes, like the very large array in New Mexico,
可以探索深度空间 are able to peer deep into space
揭示引力那无与伦比的吸引力 and reveal the incredible attractive power of gravity.
这是仙女星系 This is Andromeda,
一团跟银河系质量大小都差不多的螺旋星云 a spiral galaxy roughly the same size and mass as the Milky Way.
这个由超过一万亿恒星组成的星际孤岛 This island of over a trillion stars
距离地球逾二百五十万光年 sits over 2.5 million light years away,
但这段距离正以每小时五十万公里的速度在缩短 but every hour that gap shrinks by half a million kilometres.
虽然绝大部分星系自从大爆炸之后 Whilst most galaxies have been rushing away from each other
就开始渐行渐远 ever since they formed just after the Big Bang,
但有一些星系成型时靠得太近 some galaxies formed so close together that
于是就被引力锁到了一起 they are locked in a gravitational embrace.
银河系和仙女星系就是这种情况 And the Milky Way and Andromeda are two such galaxies.
计算机模拟结果表明 And computer simulations suggest that they will collide together
它们将在三十亿年左右融为一体 in around three billion years' time.
看 那就是模拟银河系 Look at that. That's a simulation of the Milky Way galaxy
与仙女星系融为一体的画面 and the Andromeda Galaxy colliding together,
所有甩出来的这些缕缕烟尘都是恒星 and all these wisps of smoke getting thrown out are stars.
这些是从银河系甩出来的恒星系 These are star systems getting ripped out of the galaxy
被扔进了星际空间 and thrown off into interstellar space.
这两个由数千亿恒星组成的宇宙岛 These two islands of hundreds of billions of suns
互相穿过 have flown through each other,
此时引力又略施手段 and gravity has exerted its grasp
将它们拉回原位 and dragged them back again.
记住 这些点中的某一个就是我们 And just remember that we are one of those dots.
我们的太阳 地球和太阳系 You know, our sun and the Earth and the solar system
不是将被扔进星际空间 are either going to be flung out into interstellar space,
就是会停留其中 or they're going to be in here,
停留在这个无数星球彼此环绕 in this maelstrom of hundreds of billions of suns
共同孕育新星系核心的 swirling around each other
大漩涡之中 and forming the core of a new galaxy.
试想这样一番景象 Just imagine what it would be like
当仙女星系进入我们的视野 to gaze up at the sky as Andromeda approached.
天空中闪耀着数以万亿计恒星的光芒 The sky would be ablaze with the light of hundreds of billions of suns
随之而来的剧烈碰撞所产生的能量 and the imminent collision would provide the energy
还会生成数以亿计的新星球 to generate the births of hundreds of millions more.
那将是何等壮观的景象 What a magnificent sight it would be.
然而更为气势磅礴的 But far more magnificent
便是引力包罗万象的胸怀 is the immense scale of gravity's embrace.
它跨越千亿公里的天堑 It holds galaxies together
将众多星系汇聚在一起 across hundreds of billions of kilometres
形成了宇宙中最宏伟的巨制 and, in doing so, it creates the most magnificent structures.
作为室女座星系团一部分的银河系 Our own Milky Way is part of one of these,
便是这巨制中的一页 the Virgo cluster.
画面中的每个小点都是一个星系 Every point of light in this image is not a star,
而非星球 but a galaxy.
这个星系团包含两千个星系 There are 2,000 galaxies in this cluster,
它们之间靠引力紧密相连 and they're all bound together by gravity,
成为我们邻近的星际空间中 making it the largest structure
最庞大的结构 in our intergalactic neighbourhood.
引力的作用似乎无边无界 There seems to be no limit to the reach or power of gravity.
它深深的影响力 Its influence can be felt
超越了无垠时空的界限 across the vast expanses of space and time.
但对于引力来说 有一点十分有趣 But there's something very interesting about gravity,
因为它是世上最微弱的自然力 你看 because it is by far the weakest force of nature. I mean, look.
即使有一整个地球在吸引它 I can...pick this rock up off the ground even though
我仍旧可以将这块石头轻而易举地举起 there's an entire planet, planet Earth, trying to pull it down
假若引力如此微弱 So if gravity is so weak,
又是怎样产生石破天惊的影响呢 how come it's so influential?
也许在地球上引力不甚明显 Gravity may be weak here on Earth,
但在宇宙中却强大无比 but it's not so weak across the cosmos.
这股无形的力量 This invisible force
在太阳系中的任何行星上 varies on all the planets in the solar system
以及在我们已发现的那些 and on the exo-planets
围绕各自恒星运行的系外行星上都各不相同 we've discovered orbiting other suns.
想要真实体验外星世界的重力感 To experience what gravity feels like on these worlds,
我必须来转几圈 I need to go for a spin.
这是一台离心机 This is a centrifuge.
它建于二十世纪五十年代 It was built in the 1950s to test whether fighter pilots
用以甄选战斗机飞行员 had the right stuff, but it's going to allow me to
它能让我亲身体会到 feel what it'd be like to
伫立在太阳系中那些质量 stand on the surface of any of the planets
远大于地球的星球上是何种感觉 in the solar system that are more massive than the Earth,
实际上它也能模拟 and, in fact, also what it
目前我们已发现的围绕遥远恒星运转的 would be like to stand on some of the planets
那些行星的重力环境 that we've found around distant stars.
首先我要给你系上安全带 Right, I'll have to strap you in, first of all.
你一松开它 离心机就会立刻停止 When you release it, the centrifuge will stop.
指点我的这位是F-16战斗机的飞行员 I was just told by the F-16 fighter pilot,
他也曾经历这番考验 who's just been in here,
他说坐这里比开喷气式飞机 that it's a hundred times more uncomfortable
要难受一百倍 than being in a jet fighter.
其实我有点小自信 I was kind of confident
因为我坐过喷气式飞机 because I've been in jet fighters
并没有感觉多么难受 and didn't find it too uncomfortable, but apparently,
但这回是它的一百倍 this is a hundred times worse!
舱门关闭 数据已连接 博士准备完毕 Doors closed again. Profile is there. Doctor is ready.
布莱恩 我们马上启动机器 We'll start up the centrifuge,
倒数三秒钟后 Brian, and bring you in orbit,
你将进入离心旋转轨道 and it happens in three...two...one second from now.
我的第一站是海王星 The first planet I'm travelling to is Neptune.
它的引力只比地球略大 Its gravity is just fractionally stronger than here on Earth.
这就是海王星的重力环境 So this is the gravitational field
你知道吗 我觉得 on Neptune and you feel, you know what?
我应该能适应 I could probably get used to this.
我可以在海王星表面生存下去 I could probably live on the surface of Neptune.
你能抬起你的手吗 Can you lift your hands a little?
好的 然后放下 There we go. Yeah, and down.
事实上 手明显变重了 费力多了 And it is actually quite an effort. It is noticeably heavier.
像是提着一个重物 It's like having a reasonably heavy weight in your hand.
准备好体验2.5倍的重力了吗 Are you ready to go to 2.5G?
是的 我们将要启程前往木星 Yes, so now we'll move, move from Neptune to Jupiter.
出发吧 Let's go there.
木星的体积是地球的一千三百多倍 Jupiter is over 1300 times more massive than the Earth,
但因为它的成分大多为气体 密度较小 but because it's mostly gas, it's not very dense, so its gravity
所以它的引力只有地球的两倍 is just over twice as strong at its surface.
现在 我真的很难抬起手臂 Well, now actually, it is quite difficult to lift my hand.
这就是2.5倍的重力 And that's 2.5G.
我已经觉得难以忍受了 I wouldn't want to sit here for half an hour.
你能将双手举过头顶吗 Can you lift, lift both of your hands above your head?
-看看情况如何 -你瞧 确实 - See what happens there. - Let's see, so actually...just about,
这个动作已然十分费劲 but actually, it's an immense amount of hard work.
在木星上生活实属不易 So it would be hard work living on Jupiter.
接下来是4倍重力 Let's go to 4G.
我们要去的这个星球 Actually, this is heading to a planet around,
叫做OGLE-2TRL9B a planet called Ogle-2TRL9B,
它是船底座中的一颗行星 which is around a star in the constellation of Carina.
是目前已探明的系外行星之一 It's one of the exo-planets we've discovered.
我们走吧 Oh, and there we go.
现在 我真的开始 Now, that is actually
感到不适了 beginning to feel quite unpleasant.
能描述一下你的感觉吗 Can you describe what you're feeling?
脸部异常重 Very heavy face.
头也十分沉重 My head is extremely heavy.
你的肺部 呼吸感觉如何 How about your lungs, inhaling, exhaling, breathing?
费老劲了 It's much harder work.
我没法把手抬过腿高 I can't lift my hand off my leg.
好的 OK.
-这是四倍引力吗 -是的 - And that's at 4G? - Yeah.
我的脸和手感觉无比沉重 Well, my head and my face feel very, very heavy.
这种感觉极其糟糕 It's quite an unpleasant feeling.
接下来是五倍重力环境 We'll go to five, and let
如果你出现视觉障碍 请马上告诉我 me know if you have any visual disturbances.
我正在通往一颗 I'm now on route to
新近发现的系外行星 Wasp-8B a newly discovered exo-planet, Wasp-8B.
4.4倍速 4.4.
它位于一个叫做 This world sits in the
玉夫座的小星系中 small and faint constellation of Sculptor.
连说话都困难 Quite hard to speak.
它的引力 It has a gravitational
差不多有地球的五倍 force nearly five times that of the Earth.
即将到达五倍重力环境 Right, we'll go to 5G.
-眼前模糊不清 -好的 - Very foggy. - OK.
-一片迷茫 -是吗 - Very foggy. - Very foggy?
-还是很模糊吗 -是的 - Still foggy? - Yeah.
好 Right.
-减速吧 -好的 马上减速 - Take it down. - OK, we'll take you down.
真是妙趣横生 Very interesting.
可不是嘛 It was, wasn't it?
我的脸还有点下垂吧 My face felt a bit saggy, though.
你刚看起来确实有点不一样 Well, you looked a little different.
这段时间真挺难熬的 It was quite unpleasant that time, actually.
当重力迅速升至五倍时 It went very quickly up to 5G and what happens is -
对我来说 眼前一片模糊 for me, anyway - vision becomes very, very foggy.
所有事物都混沌不清 The whole thing just blurs and blurs and blurs.
你会意识到 很显然 So you realise that we're,
显然 人类生活在重力加速度为 obviously, very finely tuned to live
一倍G时最为舒适 on a planet that has an acceleration due to gravity of 1G.
当达到两倍时 就有些许困难 When you go to 2G, it's difficult.
三倍或四倍时 情况就令人难受了 When you go to 3G and 4G, it becomes unpleasant
而五倍时 不适感几乎令我 and 5G anyway, for me, was on the border of being
要昏厥过去 so unpleasant that you pass out.
可见 虽然引力在地球上不甚明显 So, although gravity feels weak here on Earth,
但在宇宙的其它地方却并非如此 it certainly isn't weak everywhere across the universe,
这是因为引力具有加成性 and that's because gravity is an additive force.
它和质量成正比 It scales with mass,
星球的质量越大 so the more massive the planet or star,
引力就强 the stronger its gravity.
在太阳系中 The body with the strongest
引力最大的莫过于太阳 gravity in our solar system is the sun.
在相对小的体积下 Our star has so much mass
它的质量却十分惊人 packed inside a relatively small space that
这使得它的地心引力 it has a gravitational pull
达到了地球表面的28倍 at its surface 28 times that of the Earth.
如果我能踏足其上 所有血液 If I were able to set foot on this world, all the blood would be
将无法回流至上半身 poled out of my upper body,
我会在一分钟内死去 and I would die in less than a minute.
但太阳产生的引力 But our sun's gravitational
与"超级G"相比 force is nothing compared to the extreme G
简直是小巫见大巫 found at the surface of
它位于宇宙中一个极其独特的位置 one of the strangest places in the universe.
设想一个质量比太阳大 直径却不到20公里的星球 Imagine the gravity on a world with more mass than our sun,
它上面的万有引力将是怎样的呢 crammed into a sphere just 20 kilometres across.
首次侦测到这个奇观是在四十年前 We first detected such a wonder just 40 years ago,
但对它的探索早在千年之前就已开始 but the story of its discovery begins over a thousand years earlier.
这是位于美国西北部 This is Chaco Canyon in New Mexico
新墨西哥州的查科峡谷 in the south western United States,
它也是 and it was home to what's
查科文明的发源地 become known as the Chacoan civilisation.
这是博尼托城邦 Well, this is Pueblo Bonito,
查科文明时期的大府邸之一 one of the so-called Chacoan great houses.
十一世纪初 Back in the 1100s,
这个地方就拥有超过600间房屋 this place had over 600 rooms.
据推测 这个建筑用于宗教仪式 It's thought that this building must have been ceremonial
你可以把它理解为一座大教堂 or religious, a cathedral, if you like.
这些查科时期的大宅 The Chacoan great houses are
排成一列 反映了天空中的一番奇观 aligned with interesting objects in the sky,
它们就坐落在每年几个重要的时间点上 so the points at which the sun and moon rise
太阳与月亮所升起的位置 at important times of the year.
通过建造这些建筑物 So it seems that by constructing these grand buildings,
这些查科人不仅将自己 the Chacoans were not only trying to place themselves
置于当地文化的中心 at the heart of local culture,
甚至设想自己处于宇宙的中心 but also to place themselves at the heart of the cosmos.
人们对查科文化知之甚少 Very little is known about the Chacoan culture,
因为至今都没有发现任何文本记载 because no written text has ever been discovered.
但在这个峡谷的另一处 But in another part of the canyon,
记录了一件发生 there is a record of a spectacular event
于1054年的奇观 that they witnessed in the sky in 1054.
我十二三岁的时候就知道这个地方了 Now, I've known about this place since I was 12 or 13 years old,
因为我看了这本书和卡尔·萨根导演的 and the reason is this book, and the television series Cosmos,
杰出电视剧集《宇宙》 Carl Sagan's masterpiece,
也许这就是我对宇宙学 probably the most important
如此感兴趣的原因 reason that I got interested in astronomy.
在这本书的232页 And on page 232,
有这样一张照片 there's a picture that's always fascinated me
它总令我浮想联翩 and captured my imagination
照的就是那面岩墙 and it's a photograph of that wall of rock,
画面上正是岩壁突出部分的一副壁画 and in particular a painting that's on the overhang.
因为人们认为这幅壁画记录了 Because it's thought that that painting is a record of one of
宇宙中最壮观最神奇的天象 the most spectacular and magical events in the cosmos.
公元1054年7月4日 On 4th July 1054AD,
一颗明亮的新星现于天际 a bright new star appeared,
在三周多的时间里 它闪耀在夜空之中 and it outshone every other
其光芒盖过了其它所有的星星 star in the night sky for over three weeks.
光芒之盛甚至在白天都能看到 It was so bright that it was visible in the daytime,
人们认为 and it's thought that
查克人借此壁画记录了 this painting is the Chacoan people's record
那次天象 of that astronomical event.
人们之所以这么认为 The reason we think that
是因为借用现代电脑技术 is that using modern computer techniques,
你便能倒转夜空 并看到 you can wind back the night sky and say,
月亮去向何方 "Where would the moon have been?
而星辰又去向何方" Where would the stars have been?"
你会发现 在那个方向 And you find that in that direction,
月亮会从地平线升起 穿过茫茫夜空 the moon would have risen and tracked across the night sky,
而那颗新星 and the new star would have been
将与月牙咫尺相依 very, very close to the crescent moon.
我们现在知道 We now know that
事实上那是颗即将爆炸消亡的 that new star was in fact the explosive death
古老的恒星 即一颗超新星的爆炸 of an old star, a supernova explosion,
一颗恒星 在生命结束时崩塌瓦解 a star, literally, blowing itself apart at the end of its life.
纵观恒星的整个生命期 Throughout a star's life,
能量的输出和引力作用的推入 there is a constant battle between
一直在相互抗争着 energy pushing out and gravity pushing in.
只要恒星还在燃烧 这两股力量就会相互抵消 As long as the star burns, the two forces balance each other out.
但当恒星燃料耗尽时 But when it runs out of fuel,
引力占据主导 恒星开始瓦解 gravity wins and the star collapses,
其爆炸产生的光芒可与十亿个太阳相比拟 and then explodes with the brightness of a billion suns.
我们无法目睹查克人所看到的超新星 We can no longer see the supernova the Chacoans saw,
但我们仍可惊叹它留下的馈赠 but we can still marvel at what it left behind.
这是蟹状星云 即一千年前 This is the Crab Nebula, the remains of that
查克人在天空中所看到的 exploding star that the
恒星爆炸后留下的残骸 Chacoans saw in these skies a thousand years ago.
它是由气体 尘埃及那颗消亡恒星残骸 It's an expanding cloud of gas and dust, the remains
组成的不断膨胀的星云 of that dying star, and
不同的颜色代表了不同的化学元素 the colours are different chemical elements,
橙色是氢 红色是氮 so the orange is hydrogen, the red is nitrogen
这些绿色的丝状物是氧 and those filaments of green are oxygen.
随着恒星的爆炸 While the explosion blew
绝大部分星际物质喷入宇宙 most of the stellar material out into the cosmos
形成了这个巨大的星云 to form this vast nebula,
我们现在知道 故事并没有结束 we now know that this wasn't the end of the story.
在星云中心 At the centre of the nebula
存在着恒星的残骸 即受引力作用 lies the remnant of the star, its core,
挤压变形的内核 crushed by the force of gravity.
那是一颗中子星 That is a neutron star,
此图像由钱德拉X射线卫星拍摄 an image taken by the Chandra X-ray satellite.
中心圆点处只有20公里宽 The central blob there is only about 20 kilometres across,
只有一个城市大小 却与太阳质量相当 but it's got the mass of our sun, a star the size of a city.
它以每秒超过30次的频率旋转 It's spinning at a rate of over 30 times a second,
相当于每分钟自转1800圈 1,800 revolutions per minute,
它确实是一个令人惊讶的外星世界 and it really is an astonishingly alien world.
当中子星旋转时 质子的喷发物 As the neutron star spins, jets of particles
以近乎光速的速度从两极点冲出 stream out from the poles at almost the speed of light.
这些喷发物是能量强大的光束 These jets are powerful beams
它们随着恒星的自转 扫过夜空 that sweep around as the star rotates.
当光束掠过地球时 When the beams sweep across the Earth,
会发出频率规则的声响 they can be heard as regular pulses,
所以我们称之为脉冲星 so we call them pulsars.
但并不是这种富有节奏的声响 But it's not this rhythmic noise
使得蟹状脉冲星与众不同 that makes the Crab Pulsar a wonder.
而是由于其自身引力所具有的特性 It's the extraordinary nature of gravity on this alien world.
如果我身处其表面 If I were to be on its surface,
那作用在我身上的重力 then the gravitational pull on me
相当于我在地球感受到的 would be a hundred thousand
上万亿倍 million times that that I feel on Earth.
也就是说 如果我从投影屏幕上方跳下来 That means that if I were to jump from the top of that
在落地之时 projection screen, by the time I hit the ground,
我的下落速度将逾每小时四百万英里 I'd be travelling at over four million miles an hour.
其引力作用之强可见一斑 That's a lot of gravity.
脉冲星拥有如此惊人的引力 Pulsars have such extreme gravity
是因为组成它们的物质的密度极其之大 because they're made of incredibly dense matter.
为理解这点 To understand why,
就必须了解 在最微小的范围内 we have to look at what gravity can do to matter
重力对物质会起何影响 at the very smallest scales.
宇宙万物皆由原子组成 Everything in the universe is made of atoms,
直到十九世纪末二十世纪初 and until the turn of the 20th century,
人们都认为 it was thought that they
原子是组成物质最小的单位 were the smallest building blocks of matter.
"原子"这个词来源于希腊语的"Atomos" I mean, the word itself comes from the Greek "Atomos",
意思是"不可分割" which means indivisible.
我们现在知道 原子是由更微小的物质组成的 But we now know that atoms are made of much smaller stuff.
原子包括原子核 Atoms consist of an atomic nucleus
以及核外环绕的电子云 surrounded by a cloud of electrons.
原子所有的质量几乎都集中于原子核 And whilst almost all of the mass is contained in the nucleus,
而与原子相比 原子核极其微小 it is incredibly tiny compared to the size of an atom.
如果这是原子核 If this were a nucleus,
那电子云会延伸至 then the cloud of electrons would stretch out
一公里之外的地方 to something like a kilometre away.
就如从这里到那块石头的距离 I mean, that's from here to that rock.
在这种情况下 电子的体积却极其微小 And electrons on this scale are incredibly tiny.
就如同空气中的粒粒尘埃 但数量稀少 They're just like specks of dust and they're aren't many of them.
想像一下 一个巨大的球体 So imagine a giant sphere
以原子核为中心 并延伸开来 centred on the atomic nucleus stretching out
一直到那块石头以及上空 all the way to that rock and beyond,
而在其中只有几粒尘埃 with just a few points of dust in it.
这就是原子 That's an atom.
如此说来 物质中几乎空无一物 So that means that matter is almost entirely empty space.
我身体内空空荡荡 地球也是如此 I'm full of empty space. The Earth is full of empty space.
你所看到的宇宙万物 Everything you can see in the universe
几乎都空空如也 is pretty much just empty space.
如果宇宙中的物质都由原子组成 So if everything in the universe is made up of atoms,
而原子所占99.9999%的空间都空无一物 and atoms are 99.9999% empty space,
那宇宙的大部分皆是虚无 then most of the universe is empty.
但在蟹状脉冲星中 引力作用如此强烈 But in the Crab Pulsar, the force of gravity is so extreme
以至于原子内部的真空空间 that the empty space inside the atoms
全部都被挤压出去 is squashed out of existence,
而最后所剩的就是致密物质 so all you're left with is incredibly dense matter.
假设这是中子星上的物质 Imagine this was matter taken from a neutron star -
那么其质量将大于整座埃佛勒斯峰 then it would weigh more than Mount Everest.
喜马拉雅山主峰之一 中国称珠穆朗玛峰
换句话说 Or to put it another way,
如果把地球上的人类都聚集起来 if I took every human being on the planet
挤压他们的空隙 and squashed them so they were
让他们如同中子星物质一般稠密 as dense as neutron star matter,
那我们所有人都能塞入其中 then we would all fit inside that.
如果把它扔到地上 And if I were to drop my neutron star stuff to the ground,
那它会割穿地球表面 then it would slice straight through the earth
犹如刀刃切过黄油 like a knife through butter.
放眼宇宙各处 引力无处不在 Wherever we look in the universe, we see gravity at work.
它创造出形态和结构 It creates shape and structure.
掌控着每个行星 恒星及星系的运行轨道 It governs the orbits of every planet, star and galaxy
而我们自认为可以预测其运行规律 in ways we thought we were able to predict.
但我们对它的认识仍存在一个漏洞 But there was a flaw in our understanding of this force,
它可以从地球的近邻身上反映出来 and it was exposed by one of our close neighbours.
这就是水星 This is Mercury.
千万年来 当这颗"飞毛腿"星球 For thousands of years, we've marvelled
匆匆划过太阳表面时 人们都惊叹无比 as this fleet-footed planet races across the face of the sun.
但150年前 But 150 years ago,
天文学家注意到水星运行轨道的奇怪之处 astronomers noticed something strange about Mercury's orbit.
假设这块石头是太阳 这是水星 Imagine that this rock is the sun, and this is Mercury.
水星的运行轨道很复杂 Now Mercury has quite a complex orbit.
首先 它并不是正圆 For one thing it's not a perfect circle,
而是扁长的椭圆形 it's quite an elongated ellipse.
所以在其近日点 So at its closest approach to the sun,
它距太阳约四千六百万公里 it's around 46 million kilometres away,
随后运行至远日点 and then it drifts out to
即距太阳七千万公里左右 something just under 70 million kilometres.
你只需运用牛顿万有引力定律 But you can calculate Mercury's orbit very precisely
就可精确计算出水星的运行轨道 using only Newton's laws of gravity.
所以天文学家常喜欢预测 So astronomers used to predict
在什么时候 当你抬头仰望天空 the exact time when you could look up into the sky,
注视太阳时 look at the sun
能看到那如小圆盘般的水星 划过太阳表面 and see the tiny disc of Mercury pass across its face.
但事实上 他们从未预测准确 But the thing was, they never got it right.
他们一次又一次作出预测 They predicted it time and time again,
但每当此情况发生时 and every time it happened,
总会有些许偏差 真是相当尴尬 they got it slightly wrong, which was an immense embarrassment.
但没人质疑牛顿 相反他们所做的是 So what they did was that, rather than question Newton,
假想了一颗叫祝融星的行星 they invented another planet, and they called it Vulcan,
并声称在太阳系的某个角落 and they said that there must be another planet somewhere
必定存在一颗地球上不可见的行星 in the solar system, which is always invisible from Earth
它扰乱了水星的运行轨道 but which perturbed Mercury's orbit a bit,
他们就是这样解释计算错误的原因 and so that was the reason their calculations were wrong.
数十年来 天文学家不断寻找祝融星 For decades, astronomers searched and searched for Vulcan.
但他们从未找到 因为它根本就不存在 But they never found it, because Vulcan didn't exist.
而真正的解释 The explanation, the real explanation,
比自创的祝融星更加有趣 was even more interesting than inventing the planet Vulcan,
因为计算公式需要稍加修正 because it required a modification,
事实上 是对牛顿万有引力定律的彻底重写 in fact, a complete re-writing of Newton's law of gravity.
引力并非如一个巨大磁铁般 Gravity is not a force pulling us towards the centre of the Earth
把我们向地球中心吸 like a giant magnet.
在某种意义上 引力根本就不是一种力 In a sense, gravity isn't really a force at all.
如何描述引力的本质 Describing the nature of gravity
成为对人类智慧巅峰的 turned out to be one of the great
又一挑战 intellectual challenges,
但牛顿死后约二百年 新理论诞生了 but almost 200 years after Newton's death, a new theory emerged.
这个新理论被称为广义相对论 The new theory, called general relativity,
它经过阿尔伯特·爱因斯坦十年的研究 was published in 1915
于1915年发表 by Albert Einstein after ten years of work,
直到现在 此理论还被视为物理史上 and it stands to this day as one of the great achievements
最伟大的成就之一 in the history of physics.
它不仅可以绝对精确地解释 You see, not only was it able to explain with absolute precision
水星运行的异常 the strange behaviour of Mercury,
也可解释迄今为止 我们在宇宙中 but it explains to this day everything we can see
所见的任何与引力相关的现象 out there in the universe that has anything to do with gravity.
最为重要的是 And, most importantly of all,
它解释了引力是如何作用于万物的 it explains how gravity actually works.
引力是恒星 行星及星系 Gravity is the effect that the stars, planets and galaxies
对其周围空间所产生的影响 have on the very space that surrounds them.
根据爱因斯坦的理论 太空并不是空无一物 According to Einstein, space is not just an empty stage -
而是一个被称作时空的结构 it's a fabric called space-time.
这种结构可以被行星 This fabric can be warped, bent and curved
恒星和星系的巨大质量所扭曲 by the enormous mass of the planets, stars and galaxies.
宇宙中所有的物质都在扭曲宇宙 You see, all matter in the universe bends.
构成宇宙自身的物质 扭曲了空间 The very fabric of the universe itself - matter - bends space.
我使空间扭曲 这片群山也是 I bend space, these mountains bend space,
但是扭曲程度非常之微小 but by the tiniest of tiniest of amounts.
但当达到行星 恒星或者星系的规模时 But when you get onto the scale of planets and stars, galaxies,
它们扭曲宇宙结构的程度 then they bend and curve the fabric of the universe
就十分之深了 by a very large amount indeed.
最关键的一点便是 And here is the key idea.
在扭曲的时空中 Everything moves in straight lines
一切均沿直线运动 over the curved landscape of space-time.
简单来说 我们看见的行星轨道 So what we see as a planet's orbit is simply the planet
是行星在被质量极大的恒星 falling into the curved space-time
所扭曲后的时空中的运行轨道 created by the huge mass of a star.
这就为解释水星飘忽不定的轨道提供了可能 This is able to explain Mercury's erratic orbit.
因为水星离太阳很近 Because of the planet's proximity to our sun,
它受到时空扭曲的影响 the effects of the curvature of space-time matter far more
比太阳系其他行星都要巨大 for Mercury than for any other planet in the solar system.
扭曲空间的概念十分抽象 This idea of curved space is difficult to imagine,
但如果你能够迈出这里 but if you could only step outside of it,
如果我们可以凌驾于时空之上俯视它 if we could only float above space-time and look down on it,
你会发现我们的宇宙不过如此 this is what our universe would look like.
群山和深谷浮现在你的眼前 You would see the mountains and valleys.
你可以看到由行星和月亮 You would see the little peaks and troughs
雕出的精巧的峰尖和谷底 created by planets and moons,
也能领略由星系巨匠 and you would see these vast,
凿刻出的无尽深渊 deep valleys created by the galaxies.
你会发现行星 卫星和恒星 And you would see planets and moons and stars circling the peaks
在径直穿过那片扭曲的时空中的过程中 as they follow their straight-line paths
留下一串华丽的转身 through the curved landscape of space-time.
所以你可以这样考虑引力 So one way to think about gravity
宇宙中的万物 is that everything in the
都落入了时空当中 universe is just falling through space-time.
月球正在落入 The Moon is falling into
由地球质量创造的深谷中 the valley created by the mass of the Earth.
地球落入太阳创造的深谷中 The Earth is falling into the valley created by the sun,
太阳系正在落入银河系创造的 and the solar system is falling into the valley in space-time
时空深谷当中 created by our galaxy.
银河系也正落向宇宙中其它的星系 And our galaxy is falling towards other galaxies in the universe.
爱因斯坦的广义相对论是如此深奥 Einstein's theory of general relativity is so profound
如此绝美 它可以描绘出浩瀚宇宙的 and so beautiful that it can describe the structure and shape
结构和形状 of the universe itself.
更引人注目的是 该理论还能预言其本身的死亡 But remarkably, the theory can also predict its own demise,
因为它预言了 because it predicts the
一种密度极大 威力无比的物体的存在 existence of objects so dense and so powerful
它们能深度扭曲 that they warp and stretch
并拉伸时空结构 and bend the structure of space-time so much
导致时间停滞 它们还可以吞噬光线 that they can stop time, and that they can swallow light.
它们的威力如此惊人 These are objects so powerful
可以将宇宙中的其它奇景撕得粉身碎骨 that they can tear all the other wonders of the universe apart.
自文明伊始 我们便开始 Since the dawn of civilisation, we've peered at the stars
凝视夜空中的繁星 跟踪行星的运动轨迹 in the night sky and tracked the movements of the planets.
我们目睹着这熟悉的模式 We see these familiar patterns
在宇宙中一次又一次上演 repeated across the whole universe.
但当我们把天文望远镜对准绕银河系中心 But when we train our telescopes to the stars that orbit around
旋转的恒星时 不同寻常的现象发生了 the centre of our galaxy, we see something very unusual.
这是近十或二十年来 Well, this is one of the most fascinating and important movies
天文学界拍摄的 made in astronomy over
最引人入胜也是最重要的影像 这都是真实数据 the last ten or 20 years. This is real data.
这段影像中的每一个光点 Every point of light in this movie
都是绕银河系中心旋转的恒星 is a star orbiting around the centre of our galaxy.
它们被称为S星团 They're known as the S stars.
我们的太阳需要两亿年时间 Our sun takes around 200 million years to make its way
才能绕银河系旋转一周 around the Milky Way.
但S星团的一颗星仅需15年 One of these S stars takes only 15 years to go around
即可绕银河系中心转一圈 the centre of the galaxy.
它的公转速度达到每秒3000至4000千米 It's travelling at 3,000 or 4,000 kilometres per second.
现在 通过对旋转轨道的跟踪 Now, by tracking the orbits,
我们可以计算出中心物体的质量 it's possible to work out the mass of the thing at the centre.
答案使天文学家们为之一震 The answer took astronomers by surprise,
这么说并不为过 I think it's fair to say,
因为银河系中央物体的质量 because the object in the centre of our galaxy
是我们太阳的四百万倍 is four million times as massive as the sun,
而如此大的质量却聚集在了一个比太阳系还小的空间中 and it fits into a space smaller than our solar system.
体积如此之小 Now there's only one thing
而质量却如此庞大的物体 that anyone knows of that can be so small
只有一种可能 那就是黑洞 and yet so massive, and that's a black hole.
所以现在我们看到的 So what we're looking at here
其实是恒星像蜜蜂般蜂拥在银河系中央 is stars swarming like bees around a super-massive black
一个密度超大的黑洞旁边 hole at the centre of the Milky Way galaxy.
我们认为黑洞的体积可以比原子还小 We think black holes can be smaller than an atom,
质量却是太阳的数十亿倍 or a billion times more massive than our sun.
有些黑洞是恒星灭亡的产物 Some are born when a star dies.
当一颗质量大约是太阳15倍的行星塌缩时 When a star around 15 times the mass of our sun collapses...
核心的所有物质 ..All the matter in its core is crushed
都被压缩进无尽的黑暗虚空 into an infinite void of blackness
也就是通常所说的恒星型黑洞 known as a stellar mass black hole.
黑洞是时空扭曲最极端的例子 Black holes are the most extreme example of warped space-time.
它们质量如此庞大 They have such enormous mass
却被压缩在如此狭小的空间当中 crammed into such a tiny space
以至于它们对扭曲时空的贡献 that they curve space-time
比宇宙中的其它物体要大的多 more than any other object in the universe.
这些怪兽依靠自身无限的引力 The immense gravitational
可以轻而易举地将恒星撕碎 pull of these monsters can rip a star apart.
卷走其表面的物质 并将它拖入自己的轨道牢笼 They tear matter from its surface and drag it into orbit.
这些超高温的物质 This super-heated matter
在黑洞入口旋转 spins around the mouth of the black hole,
其核心喷射出强烈的辐射 and great jets of radiation fire from the core.
虽然随处都能探测到这些喷射物 Although these jets can be seen across the cosmos,
但其核心神秘的面纱却从未被揭开 the core itself remains a mystery.
黑洞导致时空深度扭曲 以至于任何物质 Black holes curve space-time so much that nothing,
即使是光 也无法逃脱 not even light, can escape.
所以它们的内部对我们来说永远是个谜 So their interior is for ever hidden from us.
但因为我们理解了物质扭曲空间的原理 But because we understand how matter curves the fabric of space,
使得用图像描绘这一切成为了可能 it is possible to picture what is happening.
在黑洞附近 空间和时间会变得荒诞不羁 Near a black hole, space and time do some very strange things,
因为在我们所知的宇宙范围内 because black holes are probably the most violent places
黑洞可能是最凶险的地方 we know of in the universe.
这条河提供了与靠近黑洞的时空 This river provides a beautiful analogy for what happens
相似的美丽景象 to space and time as you get closer and closer to the black hole.
在瀑布上游 水的流速非常慢 Now, upstream of the waterfall, the water is flowing pretty slowly.
设想它们的流速是每小时三千米 Let's imagine that it's flowing at three kilometres per hour,
而我每小时可以游四千米 and I can swim at four,
所以我比水流的速度更快 so I can swim faster than the flow
可以轻易逃脱瀑布的魔爪 and can easily escape falls.
但是随着你不断向下游移动 But as you go further and further
离瀑布越来越近 downstream towards the waterfall in the distance,
河水的流速会逐渐加快 the river flows faster and faster.
设想一下我决定从这跳入河中 Imagine I was to decide to jump into the river just there,
也就是瀑布的边缘 on the edge of the falls -
水的流速远远大于我的游速 the water is flowing far faster than I could swim.
所以无论我做什么 无论我怎么努力 So no matter what I did, no matter how hard I tried,
我都不可能游回上游 I would not be able to swim back upstream.
我会被无情地卷向瀑布的边缘 I would be carried inexorably towards the edge,
在瀑布中消失得无影无踪 and I would vanish over the falls.
这与黑洞的情形十分相近 Well, it's the same close to a black hole, because space
因为越靠近黑洞 空间被吸入的速度就越高 flows faster and faster and faster towards the black hole.
可以这么说 这里的一切 我所在的空间 Literally, this stuff, my space that I'm in,
都经由边缘被黑洞所吞噬 flowing over the edge into the black hole.
而在叫做视界线的特殊位置 And at the very special point called the event horizon,
空间以光速被黑洞吞噬 space is flowing at the speed of light into the black hole.
即使光速达到了每秒三十万公里 Light itself, travelling at 300,000 kilometres per second
也无法逃脱被吞噬的厄运 is not going fast enough to escape the flow,
只能落入黑暗的深渊 and light itself will plunge into the black hole.
当你落入黑洞之中 在穿过视界线之时 Well, as you fall into a black hole, across the event horizon,
如果你的脚先进入 then if you were going feet first,
脚的加速度将远远大于头的加速度 your feet would be accelerating faster than your head,
所以你将被拉扯变形 so you would be stretched,
变成意大利面条 and you would be quite literally spaghettified.
而一旦你进入了黑洞中心 Now as you get right to the centre,
我们所有的物理定律将全部失效 then our understanding of the laws of physics breaks down.
在我们创造的最适时空理论 Our best theory of space and time,
也就是爱因斯坦的广义相对论中描述道 Einstein's theory of general relativity,
空间和时间被无限扭曲 says that space and time become infinitely curved,
而黑洞中心将变得无限致密 that the centre of the hole becomes infinitely dense.
那个地方被称为奇点 That place is called the singularity,
我们对宇宙的理解 and it is the place where
便在那里终止 our understanding of the universe stops.
引力是宇宙万物最伟大的创造者和建设者 Gravity is the great creator, the constructor of worlds.
因为它是茫茫宇宙中 That's because it's the only force in the universe
唯一一个可以横跨浩渺的宇宙空间 that can reach out across the vast expanses of space
聚万千物质与一体 and pull matter together to make the planets,
生卫星 辟恒星 创星系的力 the moons, the stars and the galaxies.
但因为其冷酷无情 引力同时也是毁灭者 But gravity is also the destroyer, because it's relentless,
对于宇宙中绝大多数大质量物体 and for the most massive objects in the universe,
质量巨大的恒星 以及星系的中心 for the most enormous stars, and the centres of galaxies,
引力最终会压碎物质 使其消失殆尽 gravity will eventually crush matter out of existence.
"美丽"这个词很可能在物理学中被滥用了 Now, the word beautiful is probably over-used in physics.
我也可能常常把它挂在嘴边 I probably over-use it.
但我认为没有科学家会对用它来评价 But I don't think there is any scientist who would disagree
爱因斯坦的引力理论提出异议 with its use in the context of Einstein's theory of gravity.
因为这个理论描绘了这样一幅宇宙画面 Because here is a theory that describes a universe that
天空中的每一颗卫星 is bent and curved out of shape
每一颗行星 每一颗恒星 每一个星系 by every moon, every star
都在施展其才 扭曲这璀璨的星空 and every galaxy in the sky.
然而宇宙万物必须遵守这种扭曲 And everything in the universe has to follow those curves,
从质量最大的黑洞到最小的尘埃微粒 from the most massive black hole to the smallest mote of dust,
甚至到光束 even to beams of light.
但爱因斯坦引力理论最诱人的地方在于 But the most tantalising thing about Einstein's theory of gravity
它并非尽善尽美 is we know that it's not complete.
我们知道它还不是 We know that it's not the ultimate description
描述宇宙结构和形状的终极版本 of the structure and shape of the universe.
对于一名科学家来说 这才是最美丽的领域 And that, for a scientist, is the most beautiful place to be,
介于知与未知之间 on the border between the known and the unknown.
那才是宇宙真正的奇迹 That is the true wonder of the universe -
路漫漫其修远兮 吾将上下而求索 there's so much more left of it to explore.