最初 宇宙是一片黑暗 In the beginning, there was darkness.
紧接着一声巨响 混沌初开 And then, bang, giving birth
时间 空间和物质 to an endless, expanding existence
开始不断膨胀 of time, space and matter.
每天 我们都在解密这神秘莫测 Every day, new discoveries are unlocking the mysterious,
彗星撞击木星
令人疯狂的极端之地 the mind-blowing, the deadly secrets
发现新行星
流星撞地球
宇宙 of a place we call the universe.
过去和未来 The past and the future:
两处终极度假胜地 the ultimate vacation destinations.
是遥不可及的吗 But are they within reach?
几年或几十年内就能实现 It could happen within a few years or a few decades.
当你穿越时间 奇异之事便会发生 When you travel through time, strange things start to happen.
你可以想象大幅度扭曲实相 You can imagine warping things so dramatically
甚至能探访过去的自己 that you can actually visit yourself in the past.
有些人已经完成旅程 Some humans have already made the trip.
你能跃至未来 You will have jumped into the future
却无须变老 while aging very little.
这实在是很棒 That's really cool.
看我们解开时间旅行之谜 See how it's possible as we unravel the mystery of time travel.
太空时间44天 地球时间8年216天
时间旅行 Time Travel 宇宙第五季第四集
宇宙中所有的谜题 Of all the riddles of the universe,
时间旅行可能最令人费解 time travel may be the most perplexing.
时间本身对我们而言就有很大的魅力 Time itself has a lot of fascination for us.
克里福德·约翰逊 南加利福尼亚大学
于是我们想要欺骗时间 So we end up thinking of ways of cheating time and things like that,
让时光倒流 改变历史 going back in time, changing things.
时间旅行包括回到过去 Time travel could involve going back in time
和大幅度前往未来 or speeding into the future.
但是我们每个人被定格在现在 But for the moment, every one of us is frozen in the pesent.
然而 科学提供了这样的可能性 Yet, science holds out the possibility
我们也许能松动时间对我们的控制 that we might loosen the hold that time has on us.
爱因斯坦的相对论 Einstein's theory of relativity,
将时间置于中心 in which time plays a central role,
也令时间旅行成为可能 makes time travel an open question.
相对论是最佳的时间理论 Our best theory of time, which is relativity,
它本身并没有明确禁止时间旅行 doesn't explicitly forbid time travel per Se.
也许还有我们不了解的现象 It might be that there are things we yet don't understand
可以改进相对论 that will improve the theory,
但是相对论中似乎允许人们 but it seems that there are ways of constructing scenarios within relativity
回到过去 that allow you to go back in time.
回到过去看起来是不可能的 Traveling into the past seems improbable
因为时间只有一种方向 向前 because time only goes one way: forward.
物理学家称之为时间箭头 Physicists call this the arrow of time.
时间箭头实际上就是你总是能够让自己 The arrow of time is just the fact that you can always orient yourself,
肖恩·卡洛尔 加州理工学院
从过去移动到未来 moving from the past to the future.
你能记住过去 You remember the past.
记不住将来 You don't remember the future.
你能让事情发生在将来 You can cause things to happen in the future,
但是你不能让事情发生在过去 but you can't cause things to happen in the past.
如果拍摄一部日常生活之事的影片 If you took a movie of things going on in your everyday life,
比如将奶油混合到咖啡中 like mixing cream into your coffee,
然后逆时播放影片 then you played that movie backwards,
你会知道那是逆时的 it would be perfectly obvious.
奶油可以混入咖啡 但决不会自动分离 Cream mixes into coffee. It doesn't unmix.
这即是时间箭头 That's the arrow of time.
这个箭头让时间成了不可逆事件的单行道 The arrow makes time a one-way street of irreversible events,
这在日常经验中都是凭直觉知道的事情 something we know intuitively from our everyday experience.
在一张台球桌上 你可以撞球 On a pool table, you can break,
但不要期待球能够自行重组 but don't expect the balls to realign on their own.
你能搅拌一只鸡蛋 但是不能让其恢复原状 You can scramble an egg, but you can't unscramble it.
时间为何有箭头缘于物理学一项基本定律 The reason why time has an arrow is a fundamental law of physics
定律表明宇宙中所有物质 that says all things in the universe
均由有序状态向无序状态运动 move from orderly states to disorderly states.
当宇宙年龄变大 当我们由过去运动到未来 As the universe gets older, as we move from the past to the future,
过去与未来之间所有的差异 all the differences between the past and the future
都可以总结为 宇宙正在失去控制 can be summed up by saying that the universe is winding down.
宇宙是从有序整齐的状态开始 The universe is going from being orderly, very neatly arranged,
到无序混乱的状态 to disorderly and messy.
如果你有一个盘子 非常漂亮的盘子 So if you had a plate, that was a nice plate,
完整而有序 将它打碎 that was put together and orderly, it breaks.
它就变得无序 这很自然 It becomes more disorderly. That's very natural.
如果你试图复原盘子 将碎片粘在一起 And if you try to restore order by gluing the plate back together,
你的行为会向周围环境释放更多的能量 your actions release enough energy into the surrounding environment
总体来看 会在宇宙中造成更多的无序 to create more disorder in the universe as a whole.
但是时间箭头能在极端环境下弯曲 But the arrow of time can be bent in extreme conditions.
这源于爱因斯坦的相对论 It all goes back to Einstein's theory of relativity.
爱因斯坦指出 质量大的天体 Einstein showed that the gravity of massive objects
像行星 恒星 黑洞所产生的引力 like planets, stars, black holes
实际上能导致空间本身发生弯曲 can actually cause space itself to bend.
比这更令人惊异的是 More amazing than that,
爱因斯坦指出空间和时间实际上是 he showed that space and time are actually linked
连成一体的 他称之为时空 into a single something he called spacetime.
这意味着空间弯曲时 时间也随之弯曲 This means that whenever space is warped, so is time,
在宇宙中 黑洞的超强引力 and nothing in the universe can bend spacetime more
能使时空弯曲到最大限度 than the supergravity of a black hole.
你可以想象 引力场强大到 So you can imagine the gravitational field is so strong
空间和时间被弯曲至自我闭合 that space and time curl back on themselves.
于是你能从一点开始 And you can start at one point,
向前行进 然后回到你离开的那一点 go forward in time and come back at the point that you left.
当时间箭头弯曲至首尾相接 When the arrow of time bends around to meet its tail,
便形成死循环 同样事件不断重复发生 it creates an endless loop in which the same events happen over and over.
所以 如果时间自我闭合 So if this is time curling back on itself
宇宙只是一遍遍的重复 and the universe just repeats itself over and over again,
时间的每刻都在无限次的重复 every moment in time would just repeat an infinite number of times.
死循环令人万分沮丧 An endless loop would become pretty frustrating for anyone.
但是设想一下时光旅行者能够回到过去 But suppose a time traveler can land in the past
而没有永无休止的重复 without the constant repetition.
那样的话 就有其他障碍了 In that case, there are other roadblocks.
最令人费解的莫过于当我们干预 The most perplexing are the inconsistencies,
过去的事时 or paradoxes,
出现的不一致性 或者 悖论 that pop up when we start meddling with the past.
关于时间旅行不一致性的一个著名例子 A famous example of the kind of inconsistency you can get with time travel
叫做祖父悖论 is called the grandfather paradox.
当某人回到 And this is where someone goes back
其祖父年轻时 to the time of, for example, their grandfather.
想象一下我用时间机器让时光倒流 So imagine that I go back in time with a time machine
在1937年见到我的祖父 and meet my grandfather in 1937.
他正要和我的祖母约会 He's just about to go on a blind date with my grandmother.
他们以前从未见过面 They've never met before.
但我说服他不要去赴约 But actually, I convince him not to go on that date.
他对赛马很感兴趣 He's actually interested in the races,
所以我告诉他有场精彩的比赛 and so I tell him that there's an exciting race
[塞比克:传奇赛马]
圣塔阿尼塔赛马场有塞比克的比赛 with seabiscuit that's coming up at the Santa Anita track.
于是我们就一起去看那场比赛 And so we go off together to that race.
他从未遇见我的祖母 He never meets my grandmother.
那么 我会怎么样呢 So, what happens to me?
我怎么可能在出生后 How is it possible that I could have been born
回到过去 见到我的祖父 and then been able to go back in time, meet him,
并阻止我的出生呢 and stop myself from being born?
这就是一个不一致性的例子 So, there's an example of an inconsistency.
这是一个不合理的时间循环 It's a loop in time that really doesn't make sense.
但如果时间旅行是可能的 But if time travel is possible,
自然界必定会有绕过矛盾的路径 nature must have a way around the contradiction.
物理学家非常确定 One thing that physicists are quite certain of
宇宙最终是讲得通的 is that the universe ultimately makes sense.
一般说来 在所有物理学和自然科学中 In all of physics, in all of science, more generally,
事物的一致性 自我一致性 常规 consistency, self-consistency, common sense, if you like,
是项基本原则 is something that is a fundamental principle.
物理学家提出 自然至少有三种方法 Physicists have come up with at least three ways
来阻止时间旅行悖论的发生 That nature might act to prevent time travel paradoxes.
第一条很简单 自然会阻止 The first is simple: Nature prevents paradoxes
通过时间旅行回到过去的悖论发生 by making time travel into the past impossible
换句话说 悖论不可能发生 In other words, it can't be done.
另一种选择是 多重时空的奇妙想法 A different alternative is the strange idea of multiple universes.
应对回到过去的一种理论就是 One way of dealing with travel back in time
艾力克斯·菲利潘科 加州大学伯克利分校
在你进行时间旅行回到过去时 is to say that you actually enter a different parallel universe
其实是进入了另一个宇宙 after having made the journey back in time.
所以你不会对你原本的宇宙历史造成影响 So you don't affect the history of the universe from which you came.
实际上 任何会发生的事情都将会发生 In effect, anything that can happen will happen.
但发生的方式便是进入到一个平行的宇宙 But the way it happens is by entering a parallel universe.
相当奇怪的想法 Pretty bizarre thought.
第三种解决悖论的理论是 A third solution to the paradox problem
如果时间旅行是可能的 is the notion that if time travel is possible,
当你回到过去时 你不能改变历史 You just won't be able to change the past when you get there.
隐藏其后的科学可以通过将问题 The science behind this can be illustrated by reducing the problem
减化到你可以想象的最简单程度来进行说明 to the simplest situation you can think of.
就用台球桌上的球来举例 For example, balls on a pool table.
我们把台球桌假设成一台时光机 Let's set up a pool table that's like a time machine.
如果一个桌球进入到一个球袋中 If a ball enters one pocket,
然后通过虫洞 回到进入第一个球袋之前 it travels through a wormhole and can exit another pocket
从另一个球袋出来 before it entered the first pocket.
所以这就是一台时间机器 So it's a time machine.
现在假设桌球的确会进入第一个球袋 So now suppose the ball really does go through the first pocket,
并在它进入第一个球袋之前便出现的话 emerges before it entered,
那么在进入第一个球袋之前 and then hits itself before
桌球便会击中自己 it entered the first pocket.
使自己偏离方向 That would deflect it,
而无法进入第一个球袋 preventing it from entering the first pocket,
如此一来 就不可能从第二个球袋出现 and thus preventing it from having exited the second pocket
也就不可能使自己发生偏离 and done the deflection in the first place.
所以 这是一个悖论 So, it's a paradox.
然而 自洽性的想法 However, the idea of self-consistent solutions
使得我们从矛盾中摆脱 gives us a way out of this paradox.
假设桌球从第二个球袋中出现 Suppose that the ball exiting the second pocket
能且只能击中自己 can only hit itself in such a way
并使其进入第一个球袋 as to deflect it into the first pocket.
那么整个循环过程就符合自洽性 Then the whole loop is self-consistent.
就没有悖论 There's no paradox.
我们认为大自然总能 We think that nature always somehow manages
提供自洽的解决方案 to choose the solution that provides self-consistency.
换句话说 你会得到 In other words, you always get a solution
不会产生矛盾的方案 that does not produce a paradox.
如果那样的话 克里福德·约翰逊就能够 If that's the case and Clifford Johnson were able
回到1937年 to travel to the year 1937,
他也许能够见到他的祖父 he might be able to meet his grandfather.
但是 尽管他尽了最大的努力 But despite his best efforts,
他的举动也不会 nothing he does would alter the fact
改变他祖父祖母的相遇 that somehow his grandfather will meet his grandmother
因此允许克里福德的出生 to allow Clifford to be born.
-你好 -你好 - Hi. How are you? - How you doing?
以某种方式 宇宙会阻止他去改变历史 One way or another, the universe will prevent him from changing history.
当我们跃向未来时则不必担心悖论发生 But we don't have to worry about paradoxes when we travel forward,
时间箭头永远指向未来 Taking the arrow of time into the future.
向未来行进是世界上最容易的事情 Traveling forward in time is the easiest thing in the world.
每一分钟 你都在往下一分钟移动 Every minute, you move one minute forward in time.
与其他人相比 One thing we can do to change how we move forward in time
我们唯一可以做出改变的 relative to each other is to actually move
是以不同速度向前移动 at different velocities compared to each other.
时光机将我们送到未来 A time machine that takes us into the future
是根据爱因斯坦关于时间和速度的发现 is based on Einstein's discovery about time and speed.
你在空间上移动得越快 The faster you move in space,
跟其他人相比 时间对你就相对慢了下来 time, for you, slows down as compared to people standing still.
这种想法似乎很疯狂 And as mind-bending as this seems,
事实上 这是通过实验得到了证明的 It's actually been proven by experiments.
时钟被安置在快速移动的飞机或者火箭上 Clocks have been placed on rapidly moving airplanes and rocket ships,
它们以高速飞行一段距离 and they've moved over some distance at a very rapid speed.
旅行结束后 来测量原子钟 And when the atomic clocks were measured after the end of the journey,
它们已经比安置在地面同样的钟 they had progressed forward in time a little bit less
慢了一些 than similar clocks which had remained at rest on earth.
这被称作时间膨胀 The effect is called time dilation,
我们可以利用它去到未来 and we can use it to travel into the future.
事实上 已经有人这么做了 In fact, it's already been done.
俄罗斯宇航员谢尔盖·克里卡列夫 Russian cosmonaut, Sergei Krikalev
已经在绕地轨道中 has logged more than 803 days in orbit,
以每小时17,000英里的速度旅行了803天 traveling 17,000 miles an hour,
这使得他成为间旅行最长时间的纪录保持者 making him the world's record holder in time travel,
虽然从表面上来几乎看不出来 though you'd hardly know it to look at him.
实际发生的情况是 他所经历的时间中 What's actually happened is that he's about a 50th of a second slower
跟在地球上的每个人相比 in the amount of time that has passed for him
每50秒就会慢上一秒钟 compared to everyone else who's stayed on earth.
当你的速度接近光速的时候 But dilation really begins to pay off as a time machine
时间膨胀产生的作用就等同于时间机器 when you pump your speed to just under the speed of light.
地球上的时间以正常速度向前移动 The idea is to let clocks on earth move at their normal speed,
与此同时 在太空中时间向前移动要慢一些 while you're off in space and your clock is moving more slowly.
当你回到地球 你就来到了未来世界 When you get back, you're in the future.
假设说 你想去到500年后的世界 Suppose, for example, you wanted to go 500 years into the future.
要去到500年后的世界 To move 500 years into the future,
你要以接近光速99.99%速度飞行7年 you'd have to move at 99.99% of the speed of light for 7 years.
当你回到地球时 你的时间只前进了7年 When you get back, you will have aged only 7 years,
但是地球上已经过去了500年 but everything on earth will have aged 500.
但是要打造一个飞往未来的时光机 But one of the biggest problems with building a time machine
最大的问题就是要有充足的燃料 for travel into the future is finding enough fuel
以便让飞船能够以如此高的速度飞行 to boost a spaceship to speeds that high.
没有物理法则指出 There's no law of physics that says you can't
我们不能如此接近光速 go close to the speed of light,
但是 随着越来越接近光速 But your rocket ship becomes heavier and heavier
你的飞船也会变得越来越沉重 as you go closer and closer to light speed.
如此一来 就会需要更多的燃料来加速 So you require more and more fuel to accelerate
但加速的速度却越来越慢 you smaller and smaller amounts,
你需要超过无限多的能源 And you need more than an infinite amount of energy
来打破光速障碍 to actually break the light-speed barrier.
但是高速并不是去到未来世界的唯一办法 But high speed isn't the only way to zip into the future.
爱因斯坦的相对论中也阐释了 Einstein's theory of relativity says high gravity
强引力也可以减慢时间的移动 also slows down your clock,
这种引力你能在黑洞附近发现 The kind of gravity you might find near a black hole.
假如说 你在一架宇宙飞船中 Let's say you're in a spaceship,
你飞往黑洞附近 并且停留一会 and you go and you park yourself just outside a black hole for a while.
然后立刻回到地球 Once you return to earth,
你就会发现你来到了许多年以后的地球 you will notice that many, many years may have passed on earth,
事实上你的时间只过去了几周或几月而已 but only a few weeks or months will have passed in your own frame of reference.
这样就可以花很短的时间就去到未来 You will have jumped into the future while aging very little.
真酷 That's really cool.
但是高速飞行几年时间 But spending years at high speed
或利用黑洞重力仍是很缓慢的时间旅行 or near a black hole is a slow kind of time travel.
对于很多没有耐心的旅行者 For more impatient voyagers,
最好是有一种瞬间的办法 there may be an instantaneous version
那就是通过叫虫洞的捷径 by way of a shortcut through space called a wormhole
虫洞就宛如一个时间走廊一样 that could also become a corridor through time.
为了攻克时间旅行 To conquer time travel,
我们还有漫漫长路要走 验证各种奇特理论 we have to tread a long path that takes us through bizarre theories
以及异常复杂的技术 and incredibly complex technology toward a goal
以便达到某日能造出时光机的目标 that will one day make starships into time machines.
飞船也许是我们最好的选择 Starships, in fact, may be our best bet.
发射超高速火箭 让我们的时间慢下来 Shoot off in a rocket ship at super speed and let our own time slow down
而其他一切照常运行 while the rest of the world moves on.
对于这种冒险我们有着既得的利益 We have a vested interest in these kinds of adventures.
能够支持时间旅行的高速度 The high speeds that result in time travel
同时也是打破阻止我们 are also our only way of smashing a time barrier
进行星际旅行的障碍的唯一方法 that keeps us from traveling to the stars.
因为距离是如此的远 Because the distances are so huge.
我们当然希望能够以人类的时间量程 We would really like to be able to traverse giant distances in a short
艾力克斯·菲利潘科 加州大学伯克利分校
短时间内横越很遥远的距离去探索宇宙 amount of time in order to explore the universe on a human time scale.
距地球最近的星体甚至都是遥不可及的 Even the nearest stars to earth seem impossibly far away.
半人马座是最近的恒星 Alpha Centauri is the closest.
但就算是它 也有大概4.3光年遥远 But in this case, close amounts to 4.3 light-years away,
即25万亿公里 地月距离的一百万倍 25 trillion miles,100 million times farther than the moon.
如今最快的火箭需要八万年才能到达那里 Today's speediest rockets would need 80,000 years to get there,
因此速度是最大的瓶颈 so the challenge is to get there faster.
然而即使我们真的用高速星际火箭 But if we're going to use high-speed star missions
作为去未来的工具 as our way to get to the future,
仍然做不到人类所梦想的瞬时转移 it still doesn't satisfy our dream of getting there in a flash.
克里福德·约翰逊 南加州大学
利用高速移动来进行时间旅行 Achieving time travel by moving fast,
同时放慢你相对于其他人的时间流逝 and so slowing your clock down relative to everyone else,
的确是时间旅行的一种方法 is a way of achieving time travel.
这有点像瑞普·凡·温克尔 It's a little bit like Rip Van Winkle did by going to sleep
一觉醒来已在未来 and then waking up later and it's the future.
但大概还是会有人不买账 But some might think of that as cheating in a way.
这并不是我们想象的那种 It's not really the time travel that we think of,
进入走廊入口 where we perhaps go through a portal
或者拉下某个机器的手柄 or flick a lever on a machine
然后就到达了另外的时刻 and then end up at a different time.
物理学家在20世纪80年代时 Physicists did important theoretical work on
做了很多关于瞬时时间旅行的理论工作 instantaneous time travel in the 1980s
那也使得卡尔·萨根 while helping Carl Sagan,
得以充实他的小说《超时空要塞》 who was writing his novel, Contact.
这部作品描述了在宇宙中通过一种 The book imagined space travel faster than light
叫做虫洞的通道而进行的超光速太空旅行 through a corridor in space called a wormhole.
虫洞是一种构架在两个不同宇宙间的捷径 A wormhole is a kind of shortcut between two different parts of space,
使得天涯近在咫尺 which can be very far away or they can actually be close to each other.
但核心的理念是你必须能够轻易通过入口 But the key idea is that you can traverse the wormhole
以穿越虫洞 by simply going in through the entrance,
从一端进去 从另一端出来 one side of it, and coming out the other side.
在《超时空要塞》和其他众多科幻情节中 In Contact and many other science fiction scenarios,
虫洞常常以一种跨越浩瀚的宇宙 wormholes are used as tunnels to travel huge distances
连接其他星体的隧道形式出现 across the universe to other stars.
而事实上 若虫洞的两端相距不远 But a wormhole with openings close together
才是发展时间机器更好的基础 is a much better starting point for a time machine.
假设我身旁有一个虫洞 Suppose I have a wormhole right next to me.
如果我把手臂伸进其中 If I put my arm into it like this,
便会从另一端伸出来 it would emerge over there.
虫洞是制造时间机器的绝佳要素 A wormhole is a great ingredient for constructing a time machine.
虫洞时光机和高速飞船一样 A wormhole time machine would use the same
用的是瑞普·凡·温克尔的穿越方式 Rip Van Winkle trick as the very fast spaceship.
当其他人的时间正常流逝 Super speed makes your clock slow down
高速行进使你的时间放慢 while everyone else keeps on going.
它之所以能够运作是因为 It works because both ends of the wormhole
虫洞的两端总是保持同步 always have the same date and time,
绝无意外 no matter what happens to them.
你可以拿走其中一端 You can take one end of the wormhole
把它放到火箭上或者什么上 and put it on a rocket ship or something and send it off
以非常高的速度带一个来回 at very high speed and then back.
结果是 返回的时候 So what happens is that, when it returns,
它已经置身未来 it's in the future.
出发于2010年的虫洞端口 A traveling wormhole opening from the year 2010
国家花旗银行
返回地球时可能通往2510年 might end up returning to earth in the year 2510.
因为它的时间被放慢 Because its clock was so slow,
所以尽管世界经历了五百年 it aged very little
它却几乎没什么变化 while the rest of the world aged 500 years.
因此 若我走进虫洞置于过去的这一端 So now if I walk into the end of the wormhole that's in the past,
没有跟随火箭飞行的这一端 the end that didn't go on the rocket ship,
从另一端出去的时候 就将置身未来 I can come out the other end and I'd be in the future.
尽管以现在我们所能想象到的任何技术 Although each step of this scenario
去达到这种设想中的每一个步骤 might be really hard to achieve
都很困难 with any technology we can imagine,
但它们本质上与我们所知的时间 空间 it's all internally consistent in the laws of gravity
和万有引力的定律的原理都相吻合 and space and time that we understand so far.
因此可以说 虫洞时光机 So that wormhole time machine is, we would say,
是时空方程的有效解 a consistent solution of the equations of space and time.
理论上讲 反过来虫洞时光机也应可行 The wormhole time machine would work in reverse too,
让你从未来回到过去 making time travel theoretically possible from the future
也就是你出发的地方 back into the past, where you started.
我们要承认 Well, let's face it.
大部分的人对回到过去很感兴趣 Most people are interested in the idea of going backwards in time
是因为他们总想去弥补什么 Because they want to fix things.
有趣的是 以我们力所能及 The interesting thing is, though, that we can,
肖恩·卡洛尔 加州理工学院
利用物理原理 至少可以探索下 using the laws of physics, at least explore
穿越时间回到过去会是怎么样 what it would be like to travel backwards in time.
虽然我们总是想制造时间机器 and although we are preoccupied with time machines,
但是也许已经存在着自然衍生的虫洞 it may be that time travel is possible through wormholes
使时间旅行成为可能 that are natural in origin.
另一种可能性是 Another possibility,
如果我们做不出时间机器 if we can't make time machines,
也许大自然已经造就 is that maybe nature has already made them
那么我们只要去发现不就行了 and we just have to discover them.
早期的宇宙有可能发生过这种事情 What could have happened is that in the very early universe,
时间和空间扭曲交织 the nature of space and time was already twisted up in such a way
以至于有些时间循环被固化 that some of that got frozen in,
使得有朝一日我们能够对其加以利用 leaving time loops that we might be able to use as time machines
进行时间旅行 sometime in the future.
这种可能性非常有意思 So it's an interesting possibility
我们原来并不需要去制造这些东西 that we don't actually have to create these things.
但是如果我们只能自食其力呢 But what if we are left to our own resources?
我们究竟能不能制造出时间机器 Can we build a time machine at all?
如果理论指出虫洞可行 If theory says a wormhole is the way to go,
那么拿什么去做出虫洞 then what does it take to make one?
虫洞是纯理论的想法 Wormholes are speculative ideas.
我们无法写出描述虫洞的方程 We can write down the equations that describe them.
我们没指望在天文学上 We don't expect to bump into one
发现一个虫洞 in astronomy or anything like that,
但也没准儿会有惊喜 but we could be surprised.
我们推测虫洞最有可能存在的地方 Where we do expect wormholes to exist
是超显微水平意义上的 is at the submicroscopic level,
在这种水平上空间和时间波动不停 where space and time are fluctuating wildly.
因此人们能想到的办法 So what people imagine
就是捉住一个超显微虫洞 is somehow capturing
然后将其扩展至宏观尺寸 a microscopic wormhole and growing it to a larger size.
我们不知道这是否可行 We don't know if that's possible.
也不知道怎么去着手 We have no idea how to do that,
但是想得到一个大号虫洞的话 but that's probably what it would take
这不失为一个好方法 if you wanted a big-sized wormhole.
操纵虫洞所需要的科技水平 The technology we need to manipulate a wormhole
似乎遥不可及 may seem impossibly remote.
但是对那些渴望思想翱翔的人来说 But for those willing to let their imaginations roam,
至少有个地方还有一丝希望 there's a glimmer of hope in at least one place.
那就是由人类制造出的有史以来 It's where space, time and the nature of existence itself
最大最复杂的对撞机 meet in head-on collisions inside the biggest,
让空间 时间和万物在其中对撞 most complex machine ever created by man.
时间旅行的秘密 Where does the universe hide the secrets that might tell us
究竟藏在宇宙何处 how to travel in time?
人类的探索已经带领我们理解了虫洞 Our exploration has taken us through the world of wormholes
及其能够担当时间机器的可能性 and their possibilities as time machines,
现在我们要研究的是 and now we're in search of the technology
能够让时间旅行和空间旅行 that might make space travel and time travel
合二为一的技术 two sides of the same coin.
虽说当今世上尚未存在任何 If there's nothing on earth that comes close
东西近似时间机器 to being a time machine now,
但是有些东西或许有朝一日能引领我们 there is something that might one day lead us
发现全新的物理定律以确定 to new laws of physics that help us determine
是否可能进行时间旅行 If it's at least possible.
它探索宇宙的领域 It explores the universe,
并不在于宇宙网及其星系 not in the realm of the cosmic web and its galaxies,
而是由量子力学入手 but in the domain of quantum physics,
研究比最细微原子还要小百万倍的粒子 involving particles at sizes more than a million times smaller than the smallest atom.
它是物理学前沿最尖端的设备 It's the newest tool at the frontier of physics
称为大型强子对撞机 called the Large Hadron Collider.
这台大型强子对撞机是人类迄今为止 The Large Hadron Collider is the largest,
克里福德·约翰逊 南加州大学
建造的最大 最复杂的机械设备 most complicated machine ever created by humankind.
担负着协助我们 And its role is to help
研究粒子物理前沿的任务 us study the frontier of particle physics.
其工作原理实际上是让质子 What it actually does is it accelerates protons
在环内相对的方向加速行进 in two directions around the ring,
分别为顺时针和逆时针方向 one way round and the other way round,
以接近光速的速度让它们碰撞 to nearly the speed of light and then collides them.
对撞机在2009年11月投入使用 The collider went operational in November 2009,
科学家们提高其设备动力后 and as scientists ramped up the power,
其撞击能量 the energy in its collisions
在2010年3月时比最初增加了近十倍 was increased almost tenfold by March 2010,
并将于2013年后再次翻番 and it will double that sometime after 2013.
当今有关空间 时间 重力 Today's theories of space, time, gravity
和量子物理学的理论仍就残缺不全 and quantum physics are still incomplete,
而类似大型强子对撞机这样的设备 and tools like the Large Hadron Collider
能帮我们揭开素来令人费解的谜题 will help fill in the ever-puzzling blanks.
我们期待了解 This is where we expect that,
自己是否有遗漏某些理解时空的 if there's some missing physics that we need
物理知识 从而在一定程度判断 to understand spacetime in a way that will tell us
时间旅行是否可行 及其各种限制 whether time travel is possible or restricted in various ways.
我们期待籍此诞生出全新的规则 This is where we expect the new results to come from.
目的是了解已知最小粒子的运行规律 The goal is to figure out how rules governing the tiniest particles in existence
并将此规律用于了解极大之物 Also apply to the biggest things
如星球 星系以及不断膨胀的宇宙本身 like stars, galaxies and the expanding Universe itself.
如若未能对此了然于胸 Without understanding this,
那么建造时间机器就难于上青天 building a time machine might be harder
如同试图建造雷达却对电的存在一无所知 than trying to build a radio without knowing about the existence of electricity.
全世界有许多物理学家相信 There are many physicists in the world who believe
人类距掌握此知识已经不远了 that this understanding is in fact right around the corner,
唐纳德·马洛夫 加州大学圣巴巴拉分校
或许就在未来的数年或数十年内 that it could happen within a few years or a few decades.
而另一方面 On the other hand,
或许这难题之复杂超乎人类的想象 it could be that this problem is in fact much harder than we think
直到人类文明告终 and that human civilization will simply not live long enough
仍会是不解之谜 to figure out how it works.
大型强子对撞机或许还会揭示 The Large Hadron Collider might also reveal
时间旅行会受到额外维度的影响 extra dimensions that could play a role in time travel.
我们生活在三维空间 We live in three dimensions of space.
假如我们生活在二维空间 If we lived in only two dimensions,
我们的宇宙将会是一片扁平 our universe would be a flat sheet.
天体在我们看来就象是个圆圈 A sphere would look like a circle to us.
第三维度存在着 却超出了我们的视线 The third dimension would be there, but just hidden from our view.
若我们熟悉的三维外还存在其他维度 If dimensions other than our familiar three are really there,
它们肯定也在我们视线之外 They, too, are hidden.
如果我们想找到其他维度存在的实验证据 If we were to find experimental evidence for the existence of other dimensions
艾力克斯·菲利潘科 加州大学伯克利分校
如果我们能探索这些维度存在的意义 and if we were to be able to explore the meaning of these other dimensions
了解它们的作用原理 and see how they come about,
那么或许在久远的将来 it could be that far, far in the future,
这些新的物理学将被用于 this new physics would be utilized
某种崭新的旅行方式能让我们 to come up with some new form of travel that allows us
虽不能超越光速 也可以亚光速旅行 to at least get close to the speed of light barrier, if not surpass it.
以亚光速行进 Getting close to light speed
延缓我们自身的时间 may be the most promising way
或许是时间旅行最有可能实现的方式 to travel in time by slowing down our clocks.
在这方面 大型强子对撞机 In this respect, the Large Hadron Collider
无疑是领头者 is leading the way,
虽然它是从极微小开始 even if its first step is an extremely small one.
大型强子对撞机总长约17英里 The Large Hadron Collider is 17 miles around,
可把质子加速至接近光速 and it accelerates protons to nearly the speed of light.
如果想将其应用在人类身上 If you wanted to do that, but with human beings,
粗略估计 机器的长度得延伸 a rough calculation shows you'd have to scale it up
至上千光年才能能实现亚光速 to a thousand light-years around in order to do the same thing.
好比真有足够强大的宇宙飞船能带我们 This is like saying that the spacecraft powerful enough to carry us
星际旅行的的话 它会如此巨大 to the stars at that speed would be bigger
以至于船舱的长度已经超过了旅行的距离 than the distance we need to travel,
舱体已大到足以囊括附近的10万颗星体 big enough, in fact, to enclose The nearest 100,000 stars.
回归地球 光速和超光速物理学 Back on earth, the physics of light speed
与冲浪文化在加州马里布海滩不期而遇 and beyond meets surf culture on the beach In Malibu, California.
理查德·欧博斯是研究 Richard Obousy is one of the few physicists
曲速引擎原理[超光速空间弯曲飞行] who have worked on the concept
为数不多的几个物理学家之一 of faster-than-light warp drive.
他说曲速飞船航行 A warp ship, he says, rides
在空间扭曲所形成的起伏波上 a wave-like ripple of warped space,
与冲浪者驾驭浪波的原理大同小异 almost as a surfer rides a wave of water.
理查德·欧博斯 物理学家
这里的类比在于 A great analogy is with
冲浪者驾驭海浪 that of a surfer riding a wave of seawater.
身后的海浪稍微涌起时 So just as the wave behind it sort of rises up
就能推动冲浪者乘风破浪 and pushes this surfer through the ocean,
我认为这恰到好处的比喻了 I think it's a great analogy with
宇宙飞船如何通过推拉空间 how a spacecraft is mutually pulled and pushed
在宇宙中乘风破浪 through the fabric of space.
这个概念部分源于 The idea is based, in part,
宇宙空间在不断扩张的事实 on the fact that space in the universe is expanding.
假如我们能让它以人的意志扩张 If we can make it expand at will,
我们或许就能以此驱动曲速飞船 we may be able to propel a warp ship.
操纵空间在飞船的身后扩张 We make space expand behind the ship
并让其在前端压缩 and make it contract in front.
造成的扭曲空间波 The wave of warped space
会以超光速在宇宙中移动 moves through the universe faster than light,
当置身这所谓的曲速泡中 While inside a so-called warp bubble,
飞船就犹如乘客 the ship is a passenger,
这并不违反爱因斯坦的光速最快原则 never violating Einstein's rule against exceeding the speed of light.
虽然曲速引擎此时此刻仍是科学幻想 While warp drive is mostly science fiction at this point,
但其后确有某些物理学理论的支持 there is some physics behind it.
1994年墨西哥物理学家米盖尔·阿尔库比雷 Mexican physicist Miguel Alcubierre
推演出复杂的数学公式来支持它 Worked out the complex math to support it in 1994.
不幸的是 没有任何数学公式 Unfortunately, there's nothing in the math
能告诉我们如何化虚为实 that tells us how to do it.
虽然科学家们疑虑重重 And though most scientists have major doubts,
并非怀疑者都觉得曲速引擎一无是处 not all the skeptics are writing off warp drive completely.
他们指出 曲速泡或许难以实现 Warp bubbles may be impossible, they say.
但是如果有超级先进的人类 But what about super advanced beings
制造出超光速曲速引擎子弹头列车 building faster than light
能穿梭时空 前往其他星球又如何呢 warp drive bullet trains to the stars and through time?
探寻时空旅行秘密的时候 In searching for the secrets of time travel,
我们必然会提到曲速引擎理论 we inevitably meet the idea of warp drive
或者其他能超过光速的方法 or other strategies for traveling faster than light.
这是实现星际旅行梦想 It's the most sought-after solution
最受欢迎的解决方法 to the dream of star travel
可能会把任何宇宙飞船变成时光机器 and potentially turning any spaceship into a time machine.
未来最乐观的看法 The most optimistic views of the future
描绘了一幅图景 paint a picture
宇宙飞船乘着曲速泡离开地球 of spaceships riding warp bubbles
就像熟练的冲浪运动员 as easily as expert surfers
抓住海浪离开海滩一样容易 catch waves off the beaches of earth.
但是就算是乐观的物理学家 But even optimistic physicists
也必须面对一些残酷的现实 must face some harsh realities.
如果曲速船的工作原理跟冲浪类似 If surfing is an analogy for how a warp ship might work,
那么让一个冲浪新手来说得更清楚点 then watching a beginning surfer drives home a better point:
完成曲速驾驶是很困难的 achieving warp drive is very difficult.
今天早上 我上了第一堂冲浪课 This morning, I had my first surfing lesson
得出了这个结论 在某种意义上 and had this idea that. In some sense,
我们可以学会控制 we were gonna be able to manipulate,
另一方面 要靠天赋 In some sense, nature
我才能驾驭波浪 and that I was gonna be able to ride this wave
理查德·欧博斯 物理学家
它才会带着我以很快的速度穿过大海 and it was gonna carry me at great velocities across the ocean.
但现实是大海控制了我 But the reality is that the ocean manipulated me.
我很难控制它 比我预期的难太多了 It was far harder to control than I originally anticipated.
控制真是个难题 And control is a real problem,
因为科学认为 Because science says
一艘曲速太空船无法制造自己的次元护盾 a warp ship just can't make its own warp field.
有个常常被引用的问题 One of the often cited problems
在曲速驾驶模型中 with the warp drive model is the ship would be
我们可随意将太空船从泡中分离 what we call causally disconnected from the bubble.
就是说 船无法跟泡联系 That is, it could never find a way to communicate with the bubble.
所以一旦启动 它将无法关闭曲速泡 And so it could never turn the bubble off once it had started.
但是如果一艘星际飞船不必担心 But what would happen if the starship
它的曲线泡开关的话 会发生什么事呢 did not have to worry about turning its bubble on and off?
你也许可以想象 What you might imagine,
唐纳德·马洛夫 加州大学圣巴巴拉分校
一个足够先进的文明 for a sufficiently advanced civilization
并且已知足够多的物理学新原理 and given sufficient new laws of physics,
将会有某种曲速动力的电动扶梯 would be some kind of warp-drive escalator
或者走廊 当你将太空船停入 or corridor, and then when you would drop a ship
预定的曲速管道 如果你愿意 into the prearranged warp tube, if you will,
它也许可以驾驭某种波浪直到最后 it might be able to ride some wave along to the end.
它就像高速列车一样驶向其他星球 It would be like a bullet train to the stars.
它的乘用车也许比光速更快 Its passenger cars might travel faster than light,
但是无论是谁要发明它都需要几千年 But whoever invents it would need thousands of years
以亚光速建造它 at sub-light speeds to build it
要耗费超过我们想象的巨大能量 and use more energy than we can imagine.
我们也许需要使用 We would probably need to harness
至少整个星球的能量输出 at least the energy output from an entire star,
或者更多 if not a lot more than that.
肖恩·卡洛尔 加州理工学院
这些就是我们可以假设讨论的 So these are things we can talk about hypothetically,
但是还没人可以实现它 But no one has an engineering program to make it happen.
天文学家最近发现 When astronomers recently discovered
宇宙膨胀加速了 that the expansion Of the universe is accelerating,
他们推断这是由于一种神秘的暗能量推动的 They reasoned it was driven by a mysterious dark energy
它在太空中无处不在 That is part of space everywhere.
一些人暗示说新的机器 A few people have suggested that dark energy
比如星际飞船或者时光机器 can be harnessed as a power source
可以把暗能量被当作能源来使用 for exotic devices like starships or time machines.
我们并不确切地知道暗能量是什么 We don't really know what the dark energy is.
所以我们还不知道能否使用它 So it's not clear that we will never be able to harness it.
艾力克斯·菲利潘科 加州大学伯克利分校
无论如何 前导模型让人想到 However, the leading models suggest
暗能量是空间的另一种性质 that it's either a property of space itself
无法被转换 或者是某种 that can't be changed or some sort of an energy field
密度很低的能量场 which is of such low density,
每单位容积含量非常少 There's so little of it per unit volume,
使用足够的暗能量 that harnessing interesting amounts of it
是根本不可能的 will essentially be impossible.
曲速驾驶的基本要求 The bottom line when it comes to warp drives.
虫洞或者时光机器 wormholes or time machines,
导致了很多科学家的坚决反对 leads many scientists to reject them out of hand.
我们能保证他们是对的吗 Can we be sure that they're right?
尽管我们认为现在对宇宙已经了解很多 Though we think we know a lot about the universe right now,
并且确实如此 and we do.
在物理学史上 我们有很多次 There have been many times in the history of physics
由于自以为什么都知道 when we've been burned
过分自信而焦头烂额 by having too much of a self-assured sense of knowing it all.
确实有我们不能违背的物理学原理 There really are laws of physics that we can't violate,
但还有技术 But there's also technology.
你说 这太难了 You say, well, this is just too hard.
我们无法做到 We'll never be able to do it.
当科学家们这样说话的时候 And there, when scientists say things like that,
他们永远是错的 they're almost always wrong.
对我们来说更正确的说法是 It's much safer for us to say,
现有的物理学原理允许我们充满希望地 here are what the laws of physics allow us to imagine doing.
想象做某事 未来的某一天 hopefully. Someday in the future
我们将建立实现它的技术 we'll build the technology that makes it happen.
就像我们看到的 And as we've seen,
那样的未来也许很快就到了 that future may confront us very soon,
当天文学家们搜索太阳系外 As astronomers search for planets around stars
围绕恒星的行星时 outside the solar system,
离地球最近的星级系统是一对双恒星 the closest star system to earth has a binary pair of stars.
那是搜寻行星的好地方吗 Is that a good place to search for planets?
那是俄克拉荷马州俄克拉荷马市的妮可 That's just what Nicole of Oklahoma city, Oklahoma,
在"询问宇宙"栏目中提出的问题 wanted to "ask the universe," When she wrote...
行星可以存在在双恒星系统中吗 -Nicole 俄克拉荷马
妮可 那真的是个好问题 Nicole, that's a really cool question.
行星在双恒星系统中可以紧密地围绕 It turns out that a planet in a binary system can orbit
双恒星中的任何一个旋转 either one of the two stars very closely
或者可以从很远处围绕两颗恒星旋转 or it can orbit both of them from very far away,
但是它的轨道不可能在双星之间 But it can't orbit among them.
例如它不可能在双星中间形成八字形轨道 It can't do a figure eight among them, for example.
那种轨道是不稳定的 That trajectory is unstable
行星会很快偏离轨道 And the planet Would quickly get ejected.
我们也许快要发现 We may be on the verge of discovering
一颗地球大小的行星在围绕双星之一旋转 an earth-size planet around one of the two stars
离太阳最近的邻居 In the alpha centauri system,
半人马星系 the sun's nearest neighbor,
将会是一个从未有过的引人注目的原因 it would be a more compelling reason than ever before
吸引人们去探索新的高速太空航行的科学 to explore the exotic science of high-speed space voyages
以及与之相伴的时间旅行 and the time travel that goes with them.
半人马座很令人兴奋 Alpha centauri is very exciting
因为现在 Because it now appears
在各种不同的电脑模拟中 from a variety of different computer simulations,
格雷戈·朗丁 加州大学圣克鲁兹分校
表现出很有可能 that it's quite possible
存在像地球一样大的行星 that there could be terrestrial mass planets
在围绕半人马的双恒星系统旋转 orbiting both components of the alpha centauri binary system.
半人马A和B相隔很远 Alpha centauri "A" And "B" are so distant.
从地球上看它们好像互不相干 They look like a single star from earth.
但是它们真的是一对双星系统 But they're actually a binary pair.
这个系统的第三个成员是比邻星 A third member of the system is proxima centauri,
一颗红矮星被松散地束缚于主双星 a red dwarf loosely bound to the main pair.
如果你在半人马A或者 If you're sitting on a planet in the alpha centauri "A" system
B系统中的一颗行星上 or the alpha centauri "B" system,
你的夜空中甚至见不到比邻星 proxima centauri wouldn't even be visible in your night sky.
它太暗淡了 It's that dim.
半人马A和B围绕彼此旋转 Alpha centauri "A" and "B" orbit around each other.
在最近点 At their closest point,
它们的距离比 they're about 20% farther than the distance
从太阳到土星远20% from the sun to Saturn.
最远的时候 At their farthest,
它们之间比太阳到海王星的距离远20% They're 20% more distant than the sun is from Neptune.
它们和太阳一样都有适居带 Each has a habitable zone similar to the sun,
在那也许有孕育着生命的星球 where life-bearing planets could exist.
这也是人们梦寐以求的天文学圣杯 And that, after all, is a holy grail in astronomy.
能在生命周期以内 Well, a trip to the nearest stars,
去最近的星球旅行一次 for example, Alpha Centauri,
比如 半人马座 that we can do within our lifetimes
无疑会令人激动不已 would be immensely exciting.
科学最重要的任务之一就是 One of the great goals of science is to find life
在宇宙的其它角落发现生命 elsewhere in the universe.
要跨出第一步 除了我们的太阳系 What better place to start,
还有哪能比离我们最近的星球 other than our solar system,
更加合适呢 than the nearest star?
现在太空旅行变成了时间旅行 But now space travel becomes time travel
我们希望通过已知的物理定理 as we set our sights on a mission that can be done
来解决这个难题 under the laws of physics we now know:
也就是在45天内 a mission that can cross
行驶4光年以上的距离 more than 4 light-years of space in just 45 days.
为了解开时间的秘密 Our quest to unravel the mysteries of time
我们又回到了太阳最近的邻居 now point us again to Alpha Centauri,
半人马座上 the sun's closest neighbor.
它最有可能成为 It is the most likely
地球星际飞船的第一个目的地 first destination for a starship from earth,
飞船的这趟航行就是 a starship whose mission cannot avoid
一次完整的时空旅行 a component of time travel.
我们还不清楚通过怎样的技术手段 We have no idea what kind of technology
能让我们往返于半人马座和地球 would actually take us from here to Alpha Centauri and back.
肖恩·卡洛尔 加州理工学院
就算我们能以光速的99.99% and say that we just move at 99.99% the speed of light
一路飞过去再一路飞回来 all the way there and then all the way back.
对于要做这种长距离航行的飞船来说 The ship seems surprisingly small
实在是太小了 for one that has to make such a long trip.
在航行期间 它如何向乘员提供充足的供给 How can it hold enough supplies to support a crew for the duration?
当然没问题 因为它不仅仅是艘星际飞船 It can, because it is not only a starship,
还是台时光机器 it is also a time machine.
航行要花费8.6年的时间 It would take about 8.6 years,
因为半人马座距离我们4.3光年远 because Alpha Centauri is 4.3 light-years away.
但对于飞船上的人来说 But to the people on the ship,
只用了不到两个月的时间 It would take less than two months.
大约只要45天 It would take about 45 days
因为他们在以接近光速的速度航行 because they're traveling close to the speed of light.
为了迅速达到接近光速的速度 The astronauts would also have to overcome the problem
宇航员必须克服致命的加速度 of killer acceleration in quickly reaching the speed of light.
否则 只能缓慢的加速 Otherwise, they'd have to speed up slowly,
这大大增加了航行时间 adding time to the total trip.
对于想为星际旅行寻找港口的地球人来说 Alpha Centauri is the go-to destination for earthbound beings,
半人马座是个令人向往的目的地 hoping for a toehold in star travel.
绝非偶然的是 在詹姆斯·卡梅隆的电影阿凡达中 It's no accident that James Cameron chose it as home
虚构的星球潘多拉 to his fictional moon,
被设置成半人马座星系中的一颗卫星 Pandora, in the movie Avatar.
我们之所以要飞往半人马座 The reason we would go to Alpha Centauri has to do with today's
与现在望远镜围绕半人马座B星进行的大量 intensive telescope search for earth-like planets
类地行星搜寻不无关系 around Alpha Centauri "B"
它是半人马座系统中主双星之一 one of two stars in the system's main binary pair.
到目前为止 要在整片天空中 Alpha Centauri "B" it turns out,
寻找小质量类地行星 is by far the best star in the entire sky
格雷戈·朗丁 加州大学圣克鲁兹分校
半人马座B星是最好的目标 for searching for low-mass, earth-like planets.
不过要完成这种搜寻 But to carry out that kind of search requires
需要付出巨大的努力 a very dedicated effort.
这可不是你用望远镜观察几个晚上 It's not something that you can accomplish
就能完成的事情 in a few nights with a telescope.
要想从一张航天照片中区分半人马座的两颗主星 It's hard enough to separate the two main stars
十分困难 of Alpha Centauri in a space photograph.
而想在两颗星中一颗的周围寻找一颗地球大小的行星 Trying to see an earth-size planet around one of them
在现在来看 是不可能的 is, at the moment, impossible.
想找到这种星球 最好的机会是摆动侦测法 The best shot we have is to find the planet by the wobble method,
它能侦测出由每颗星球自身微小的引力而引起的 detecting a star's subtle back-and-forth motion
星体细微的往复摆动 caused by the tiny gravitational tug any planet would have on it.
与时间旅行一样 这几乎是不可能的任务 Like time travel, it seems almost undoable.
我们想侦测的这种往复摆动 The back-and-forth wobble,
相当相当的细微 that we need to detect is incredibly small.
我现在在玫瑰碗球场 I'm here at the Rose Bowl
如果把半人马座的大小比作这座球场 and if the Rose Bowl were the size of Alpha Centauri,
那我们需要侦测的摆动 then the amount of wobble
差不多有 that we need to detect is about this much,
3.3英寸大 而且还是从 about 3.3 inches, and we need to detect that
四百三十万英里外侦测这么点大小 from 4.3 million miles away.
半人马座B星比A稍微小一点 Alpha Centauri "B" is slightly smaller than "A"
侦测行星的行动也集中在那 and the planet hunt is concentrated there,
主要是因为较小的星球会表现出更多的摆动 mostly because a smaller star will show more wobble
会让侦测轻松许多 and detection will be that much easier.
在三到五年内 真相应该就能揭晓了 In three to five years, we should have an answer.
如果将来我们发现了一颗 I think that if we were to discover that there's
地球质量级的星球围绕着最靠近恒星运动 an earth-mass planet orbiting the very nearest star,
这将会是一件激动人心的事 then there would be a great deal of excitement to somehow
人们会设法建立大型望远镜观测它 either build a large telescope to try to observe that planet
或在遥远的未来酝酿出一个 or perhaps in the far future to design a mission
造访它的计划 that could actually go there.
尝试时间旅行的目标明确以后 With the goal of our time travel quest identified,
可以想象 地球轨道上的宇宙飞船 we can imagine our spacecraft in earth orbit,
将会飞往它们的第一个任务目标 半人马座 about to leave on the first mission to Alpha Centauri.
超高的速度让飞船成了时光机器 The ship's high speed propels it into time machine mode,
船上的时钟变慢 因此 slowing its clock, so its passengers approach
乘客在三或四周内就能抵达半人马座 Alpha Centauri in three or four weeks,
他们还能近距离欣赏到人类从未见过的景象 seeing things up close no human has ever seen before.
首先看到的是人马座的比邻红矮星的耀斑 First up, a stellar flare from the red dwarf, Proxima Centauri.
它处在三星系统的外围 On the outskirts of the triple system,
是三颗星中离太阳最近的一颗 it is the closest of the three to the sun.
人马座的比邻星经常发生突然的喷发 Proxima Centauri is prone to these sudden outbursts
这使得它在一天的时间里 that can cause it to brighten up
就能突然变亮四五次 by a factor of four or five over the course of just a day
然后又迅速黯淡下来 and then fade back just as quickly.
因此 当你们经过半人马座比邻星时 So you might be in for some real fireworks
就可能处在真正的"烟花"中 as you pass by Proxima Centauri.
艾力克斯·菲利潘科 加州大学伯克利分校
可以设想 飞船能绕过半人马座A星 we might imagine swinging past Alpha Centauri "A"
并在引力的帮助下 and using gravity assist
朝半人马座B星方向驶去 to send us in a direction of Alpha Centauri "B".
航行的终点是地球的姐妹星 The sister earth at the ship's destination
也是我们的最终目标 is the ultimate goal,
旅行者们急于探索它 希冀发现上面的生命 and the travelers will be anxious to explore it and search for life.
尽管旅行者们的旅途只花了 Although the trip has taken
几个多月的时间 little more than a few months for the travelers,
但是超高的速度大大减慢了他们的时钟 the high speed will slow down their clocks
那意味着 当他们返回时 so much, that when they return,
地球上已经流逝了将近十年的时间 nearly a decade will have passed on earth.
实现高速星际旅行的梦想 The realization of star travel at high speed
只能留给遥远的未来去实现 is a dream for the far future.
在一个技术先进 发展迅速的世界里 On an earth where technology is so advanced and changing so fast,
八或十年的时间里 足以发生戏剧性的变化 the difference of 8 or 10 years could be dramatic.
那时时空旅行也许会成为 This kind of time travel may become routine
新一代星际旅行者的家常便饭 to a new generation of star travelers...
人类也将在探索宇宙这一壮阔的旅途中 Taking mankind on the next giant leap
向下一个伟大的目标进发 in its epic journey through The Universe.