与霍金一起探索宇宙\N《时间旅行》（中英文字幕对照）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, 有时也是一个梦想家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.自由地去探索宇宙Free to explore the universe探究深奥的问题and ask the big questions.比如时间旅行可能吗Such as is time travel possible?我们能打开通往过去之门吗Can we open a portal to the past?或者找到通往未来的捷径\ Or find a shortcut to the future?我们最终能利用Can we ultimately use the laws of nature自然规律操纵时间吗to become masters of time itself?一起去探索吧Check it out.时间旅行时间旅行曾一度被当作科学邪说Time travel was once considered scientific heresy.由于害怕被贴上科学怪人的标签I used to avoid talking about it我过去常常避免谈及此事for fear of being labeled a crank.现如今我不会再顾虑这些But these days, I'm not so cautious.实际上我更像是建造巨石阵的那些人In fact, I'm more like the people who built stonehenge.我对时间着迷了I'm obsessed by time. 若我有台时间机器If had a time machine我想去拜访鼎盛时期的玛丽莲·梦露I'd visit Marilyn Monroe in her prime或者去拜访正用望远镜or drop in on Galileo as眺望星空的伽利略he turned his telescope to the heavens.我甚至想穿越到宇宙的尽头\ Perhaps I'd even travel to the end of the universe去探寻宇宙的完整故事结局to find out how our whole cosmic story ends.要验证这些想法能否实现To see how this might be possible,我们需要像物理学家那样we need to look at time as physicists do以四维的角度看时间as the fourth dimension.四维时空并不像听起来那样令人费解It's not as hard as it sounds.所有的物体甚至是我和我的椅子All physical objects, even me and my chair,都是三维的exist in three dimensions.任何事物都有宽度高度和长度Everything has a width and a height and a length.但是还存在另一种维度即时间维度But there is another kind of length -- a length in time.与人类的80余年寿命相比While a human may survive for 80 years,这些石头延续得更久远these stones will last much longer甚至长达数千年-- for thousands of years.而太阳系则能达到数十亿年And the solar system will last for billions of years.所有事物在时间上都有长度Everything has a length in time,在空间内同样如此as well as space.时间旅行意味着Traveling in time means穿越第四维时空traveling through this fourthdimension.为更好地理解我们以日常旅行为例To see what that means, let's do a bit of normal来直观体会一下四维时空的含义everyday traveling just to get a feel for it.一辆高速行驶的车能让实验变得更生动 A fast car makes it a bit more fun.在一条直线上行驶是在一维空间内Drive in a straight line, and you're traveling in one dimension.左转或右转就增加了第二维空间Turn right or left, and you add the second dimension.在蜿蜒的山路上下颠簸Drive up or down a twisty mountain road,就增加了高度的维度and that adds height.这样就算是在三维空间内行驶了So that's traveling in all three dimensions.但我们究竟要怎样才能实现时间旅行呢But how on earth do we travel in time?怎样才能找到一条How do we find a path通往第四维空间的路呢through the fourth dimension?让我们用一个小小的科幻情节放松一下Let's indulge in a little science fiction for a moment.时间旅行的电影里通常会Time-travel movies often出现一个巨型高耗能机器feature a vast energy-hungry machine.这台机器开辟了一条通往四维空间的道路The machine creates a path through the fourth dimension,一条时间隧道a tunnel through time.翻译：super zhanginfo vividx 取子小Q 初校：amira精校：super时间旅行者是勇敢者 A time traveler, a brave,也许也算是准备踏入perhaps foolhardy individual未知空间的愚勇之士prepared for who knows what,义无反顾地踏入时间隧道step into the time tunnle在未知的时间再现\ and emerges who knows when.这种构想兴许有些牵强The concept may be far-fetched,现实也可能与此大相径庭and the reality may be very different than this,但想法本身并没那么疯狂but the idea itself is not so crazy.物理学家也一直在为时间隧道绞尽脑汁Physicists have been thinking about tunnels in time,too,不过我们要从另一个角度来揭示这个问题but we covered it from a different angle.我们不知道在自然法则允许范围内We wonder if portals to the past or the future是否可能出现通往过去或未来的大门could ever be possible within the laws of nature.事实上As it turns out,我们认为有可we think they are.甚至给他们命名\ What's more we even give them a name:虫洞wormholes.事实上虫洞无处不在The truth is the wormholes are all around us,只不过它们微小至肉眼难以看到only they are too small to see.虫洞非常微小Wormholes are very tiny,它们存在于时间和空间的各个角落they accur in nooks and crannies in space and time. 你或许不敢苟同但请继续看You might find it tough concent, but stay with me.任何东西都不是平坦或者实心的Nothing is flat or solid.如果你仔细观察\N{\fn方正综艺简体}If you look close enough at anything,就会发现小洞和细缝无处不在you'll find holes and crannies in it.这是最基本的物理原理It's a basic physical principle对时间也同样适用and it even applies to time.看这个桌球台Take this pool table.表面看起来平整光滑但靠近了看Thesurface looks flat and smooth, but up close,实际并非如此it's actually anything but.它的表面布满了裂缝和小孔It's full of gaps and holes.就连桌球这样的光滑事物Even something as smooth as a pool ball都有小的裂缝细纹和小孔has tiny crevices, wrinkles, and voids.显而易见\ Now, it's easy to show that这在三维空间里毋容置疑this is true in the first three dimensions,但是相信我but, trust me,在第四维空间里这也是正确的it's also true of the fourth dimension, as well.在时间空间里There are tiny crevices, wrinkles, and voids也有小的裂缝细纹和小孔in time.不断地缩到最小的范围Down at the smallest of scales,甚至比分子原子还微小时smaller even than molecules,我们所得到的smaller than atoms, we get to a place就是量子泡沫called the quantum foam.虫洞就存在于此This is where wormholes exist.在量子的世界里Tiny tunnels, or shortcuts, 穿越时空的微小隧道或捷径through space and time constantly form,不断地形成消失再形成disappear, and reform within this quantum world.它们实际上连接了两个独立的区域And they actually link two separate和两处不同的时间places and two different times.不幸的是这种真实存在的时间隧道Unfortunately, these real-life time tunnels are 只有10的-33次方厘米的大小just a billion trillion trillionths of a centimeter across --远不足以容纳人类通过way too small for a human to pass through.但虫洞时间机器的概念正带来更多灵感But here's where the notion of wormhole time machines is leading. 一些科学家认为或许可以捕捉Some scientists think it may be possible to其中一个虫洞将其放大数万亿倍capture one and enlarge it near trillions of times让它大到足以能让人类to make it big enough for a human甚至宇宙飞船进入or even a spaceship to enter.假设有足够的能量和高科技Given enough power and advanced technology,或许可以在宇宙中构造一个巨大的虫洞perhaps a giant wormhole could even be constructed in space.我不是说这一定可行I'm not saying it can be done,但如果真能面世but if it could be,它将是一个非常卓越的机器it would be a truly remarkable device.一端在地球附近One end could be here near the earth,而另一端则在遥远的星际and the other far, far away, near some distant planet.理论上虫洞能够发挥更多用途Theoretically, a wormhole could do even more.如果两口开在同一个地方If both ends were in the same place and separated by没有距离阻隔但却处在不同时间time instead of distance,飞船则可以还在地球附近起降a ship could fly in and come out still near the earth,却已穿越到远古but in the distant past.或许恐龙将有幸目睹飞船着陆Maybe dinosaurs would witness the ship coming in for a landing.此时我意识到用四维空间去思考并非易事Now, I realize that thinking in four dimensions is not easy and虫洞也是令人费解的复杂概念that wormholes are a tricky concept to wrap your head around.不过请再坚持一下But hang in there.我曾构想出这样一个简单的实验I've thought up a simple experiment that could能够揭示在目前抑或今后reveal if human time travel through a wormhole is possible now,人类能否通过虫洞穿越时间or even in the future.。