TED2011
Janna Levin: The sound the universe makes
詹纳·莱文：宇宙的声音
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我们认为宇宙是寂静无声的。但物理学家詹纳·莱文告诉我们，宇宙有着自己的配乐 -- 一部声音的作品，它记录着那些外层空间中最为激动人心的事情。（比如，黑洞在撞击时空的过程中发出的“鼓声”。）一种能被人强烈感知到的声音正穿越宇宙，向我们走来。
Janna Levin - Physicist
Janna Levin is a professor of physics and astronomy at Barnard, where she studies the early universe, chaos, and black holes. She's the author of “How the Universe Got Its Spots" and the novel “A Madman Dreams of Turing Machines.” Full bio
Janna Levin is a professor of physics and astronomy at Barnard, where she studies the early universe, chaos, and black holes. She's the author of “How the Universe Got Its Spots" and the novel “A Madman Dreams of Turing Machines.” Full bio
Double-click the English transcript below to play the video.
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I want to ask you all to consider for a second
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我希望大家能花点时间考虑
00:18
the very simple fact
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一个非常简单的事实
00:20
that, by far,
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那就是，到目前为止，
00:22
most of what we know about the universe
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我们对宇宙的大部分了解
00:24
comes to us from light.
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都来自于光。
00:26
We can stand on the Earth and look up at the night sky
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我们站在地球上仰望夜空
00:29
and see stars with our bare eyes.
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用肉眼就能看到天上的繁星。
00:32
The Sun burns our peripheral vision.
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强烈的阳光是如此地刺眼，
00:34
We see light reflected off the Moon.
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我们能看到从月球反射回来的光，
00:37
And in the time since Galileo pointed that rudimentary telescope
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自从伽利略将他那简陋的天文望远镜
00:41
at the celestial bodies,
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瞄准宇宙中的天体，
00:44
the known universe has come to us through light,
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时至今日，我们所了解的宇宙，
00:47
across vast eras in cosmic history.
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通过光呈现在我们眼前。
00:50
And with all of our modern telescopes,
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在现代天文望远镜的帮助下，
00:53
we've been able to collect
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我们已经能够搜集
00:55
this stunning silent movie of the universe --
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炫目无声的宇宙影像 –
00:58
these series of snapshots
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这一系列影像
01:01
that go all the way back to the Big Bang.
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可以一直追溯到大爆炸。
01:04
And yet, the universe is not a silent movie
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不过，宇宙不是一部默剧，
01:07
because the universe isn't silent.
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因为宇宙并非真的寂静无声。
01:09
I'd like to convince you
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我想告诉大家
01:11
that the universe has a soundtrack
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宇宙有着自己的配乐，
01:13
and that soundtrack is played on space itself,
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而宇宙自身正在不停地播放着。
01:17
because space can wobble like a drum.
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因为太空可以想鼓一样振动。
01:20
It can ring out a kind of recording
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所以当一些重大事情发生时
01:23
throughout the universe
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它能够向宇宙
01:25
of some of the most dramatic events as they unfold.
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发出一系列声音。
01:28
Now we'd like to be able to add
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如今，我们希望能够
01:31
to a kind of glorious visual composition
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给这部关于宇宙的
01:34
that we have of the universe --
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宏伟的视觉作品
01:36
a sonic composition.
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配上声音。
01:38
And while we've never heard the sounds from space,
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虽然我们从未听到过来自外太空的声音，
01:42
we really should, in the next few years,
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但我们应该能够在接下来的几年内，
01:45
start to turn up the volume on what's going on out there.
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把音量调大，听听那儿究竟发生了什么。
01:47
So in this ambition
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针对捕获宇宙声音
01:49
to capture songs from the universe,
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这个远大的目标，
01:52
we turn our focus
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我们将我们的重点
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to black holes and the promise they have,
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放在黑洞以及它所表现出的前景，
01:56
because black holes can bang on space-time
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因为黑洞能够撞击时空
01:59
like mallets on a drum
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就像鼓槌撞击鼓面一样
02:01
and have a very characteristic song,
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发出非常特别的声音，
02:03
which I'd like to play for you -- some of our predictions
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我也非常高兴给你们播放一些
02:06
for what that song will be like.
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我们预测的声音。
02:08
Now black holes are dark against a dark sky.
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黑洞在漆黑的宇宙中，
02:11
We can't see them directly.
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是无法被看见的。
02:13
They're not brought to us with light, at least not directly.
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它们无法通过光直接被我们看到，至少我们不能直接看到。
02:16
We can see them indirectly,
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我们可以间接地看到，
02:18
because black holes wreak havoc on their environment.
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因为黑洞能够扭曲它们周围的事物。
02:21
They destroy stars around them.
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它们能摧毁附近的恒星。
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They churn up debris in their surroundings.
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搅动周围的碎片。
02:26
But they won't come to us directly through light.
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但它们不会通过光被我们发现。
02:28
We might one day see a shadow
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将来的某一天我们有可能可以看到一个影子
02:30
a black hole can cast on a very bright background,
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一个黑洞可以在一个非常明亮的背景上留下影子，
02:33
but we haven't yet.
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但目前还没被观测到。
02:35
And yet black holes may be heard
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尽管黑洞并不能被看到
02:37
even if they're not seen,
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但它们有可能被听到，
02:39
and that's because they bang on space-time like a drum.
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这是因为它们像鼓一样撞击时空。
02:43
Now we owe the idea that space can ring like a drum
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宇宙能发出鼓一样声音的这个想法来自于
02:46
to Albert Einstein -- to whom we owe so much.
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阿尔伯特·爱因斯坦，其实我们的很多想法都来自于他。
02:49
Einstein realized that if space were empty,
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爱因斯坦意识到如果宇宙是空的，
02:51
if the universe were empty,
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如果宇宙是空的，
02:53
it would be like this picture,
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它将看起来像这幅照片一样，
02:56
except for maybe without the helpful grid drawn on it.
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除了那些画在上面的辅助线。
02:59
But if we were freely falling through the space,
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但如果我们在宇宙中自由落体，
03:02
even without this helpful grid,
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即便没有这些辅助线，
03:04
we might be able to paint it ourselves,
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我们的轨迹也会画出这些线，
03:06
because we would notice that we traveled along straight lines,
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因为我们将会发现我们沿着直线运动，
03:09
undeflected straight paths
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沿着不发生弯折的直线
03:11
through the universe.
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穿过宇宙。
03:13
Einstein also realized --
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爱因斯坦还意识到－
03:15
and this is the real meat of the matter --
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这可是真正最关键的部分（matter也有“物质”的意思）–
03:17
that if you put energy or mass in the universe,
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如果你在宇宙中放入能量和物质，
03:20
it would curve space,
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宇宙就会弯曲。
03:22
and a freely falling object
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自由落体的物体
03:24
would pass by, let's say, the Sun
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在经过向太阳这样的天体时
03:26
and it would be deflected
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将会被偏转
03:28
along the natural curves in the space.
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沿着空间中被弯折的路径运动。
03:30
It was Einstein's great general theory of relativity.
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这就是爱因斯坦伟大的广义相对论。
03:34
Now even light will be bent by those paths.
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甚至光的路径也会被弯折。
03:37
And you can be bent so much
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当弯折大到一定程度时
03:39
that you're caught in orbit around the Sun,
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就会围绕着太阳运动的轨道转，
03:41
as the Earth is, or the Moon around the Earth.
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就像地球绕着太阳转，月球绕着地球转。
03:43
These are the natural curves in space.
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这是宇宙中自然的曲线。
03:46
What Einstein did not realize
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不过爱因斯坦并没有意识到
03:48
was that, if you took our Sun
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如果你把太阳
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and you crushed it down to six kilometers --
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压缩成直径6公里的球 –
03:53
so you took a million times the mass of the Earth
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也就是说你把相当于地球质量一百万倍的物质
03:56
and you crushed it to six kilometers across,
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压缩成直径6公里的球，
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you would make a black hole,
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你将制造出一个黑洞，
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an object so dense
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这个物体的密度非常之大
04:03
that if light veered too close, it would never escape --
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以至于如果光离它太近，也将无法逃脱－
04:06
a dark shadow against the universe.
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在宇宙中留下一个巨大的黑影，
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It wasn't Einstein who realized this,
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其实意识到这一点的人并非爱因斯坦，
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it was Karl Schwarzschild
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而是卡尔·史瓦西
04:13
who was a German Jew in World War I --
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他是一个德国犹太人，在一战中–
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joined the German army already an accomplished scientist,
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他加入德军，在俄国前线工作，
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working on the Russian front.
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那时已经是位非常杰出的科学家了。
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I like to imagine Schwarzschild in the war in the trenches
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我乐于想象史瓦西躺在战壕里
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calculating ballistic trajectories for cannon fire,
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计算着加农炮的弹道轨迹，
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and then, in between,
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然后再时不时地，
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calculating Einstein's equations --
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算算爱因斯坦方程–
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as you do in the trenches.
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试想一下那是什么样的一个情景。
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And he was reading Einstein's recently published
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他当时正在读爱因斯坦刚发表的
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general theory of relativity,
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广义相对论，
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and he was thrilled by this theory.
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他被这个理论震惊了。
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And he quickly surmised
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并且很快推导出
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an exact mathematical solution
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一个精确的数学解
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that described something very extraordinary:
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描述了一个非常异常的结果：
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curves so strong
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如果弯折过于强烈
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that space would rain down into them,
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宇宙将向内部塌陷，
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space itself would curve like a waterfall
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宇宙本身将弯曲得像一个瀑布一样
04:53
flowing down the throat of a hole.
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流入一个洞中。
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And even light could not escape this current.
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光甚至都不能逃脱这股暗流。
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Light would be dragged down the hole
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光会被拉入这个洞中
05:00
as everything else would be,
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就像其他所有东西一样，
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and all that would be left would be a shadow.
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唯一留下的只是一个影子。
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Now he wrote to Einstein,
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他写信给爱因斯坦，
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and he said, "As you will see,
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他说：“正如你将看到的，
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the war has been kind to me enough.
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战争对我还是挺仁慈的，
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Despite the heavy gunfire,
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尽管周围的炮火很猛烈。
05:14
I've been able to get away from it all
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但我已经习惯了不去想它
05:16
and walk through the land of your ideas."
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把精力用来思考你所提出的想法。”
05:19
And Einstein was very impressed with his exact solution,
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爱因斯坦被他的精确解深深吸引，
05:22
and I should hope also the dedication of the scientist.
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我想同时也被他那种科学家的执着所吸引。
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This is the hardworking scientist under harsh conditions.
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这是一个在恶劣环境中仍努力工作的科学家。
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And he took Schwarzschild's idea
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爱因斯坦第二周将史瓦西的想法
05:30
to the Prussian Academy of Sciences the next week.
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带到了普鲁士科学院。
05:33
But Einstein always thought black holes were a mathematical oddity.
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不过爱因斯坦一直认为黑洞只是一个数学奇点。
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He did not believe they existed in nature.
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他并不相信真的存在黑洞。
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He thought nature would protect us from their formation.
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他相信大自然会阻止黑洞的形成以保护我们。
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It was decades
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人们在数十年之后
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before the term "black hole" was coined
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才开始使用“黑洞”这一名词
05:46
and people realized
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并且意识到
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that black holes are real astrophysical objects --
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黑洞是真实存在的天体 –
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in fact they're the death state
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事实上，它们是一些质量极大的恒星
05:52
of very massive stars
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在它们生命的终点
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that collapse catastrophically
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发生灾难性坍缩后的
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at the end of their lifetime.
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死亡状态。
05:58
Now our Sun will not collapse to a black hole.
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我们的太阳不会坍缩形成黑洞。
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It's actually not massive enough.
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它的质量其实不足够大。
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But if we did a little thought experiment --
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但是，如果我们做了一些思想实验 –
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as Einstein was very fond of doing --
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爱因斯坦非常喜欢这样做 –
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we could imagine
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我们可以假想
06:08
putting the Sun crushed down to six kilometers,
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把太阳粉碎后压缩在六公里的范围内，
06:11
and putting a tiny little Earth around it in orbit,
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然后在围绕它的轨道上放一个小小的地球，
06:14
maybe 30 kilometers
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比如放在离黑洞太阳
06:16
outside of the black-hole sun.
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30公里远的轨道上。
06:19
And it would be self-illuminated,
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地球将自己发光，
06:21
because now the Sun's gone, we have no other source of light --
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因为现在太阳已经不见了，我们没有其他光源 –
06:23
so let's make our little Earth self-illuminated.
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因此，我们小小的地球得自己发光。
06:26
And you would realize you could put the Earth in a happy orbit
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你会发现，你甚至可以把地球放在离黑洞
06:28
even 30 km
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30公里外的轨道上
06:30
outside of this crushed black hole.
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并且让它开心地绕轨道运行。
06:33
This crushed black hole
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这个黑洞
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actually would fit inside Manhattan, more or less.
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其实只有差不多曼哈顿那么大。
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It might spill off into the Hudson a little bit
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在它摧毁地球之前，
06:39
before it destroyed the Earth.
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它可能会膨胀到哈德森大街。
06:41
But basically that's what we're talking about.
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但基本上这就是我们在讨论的东西。
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We're talking about an object that you could crush down
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我们讨论的是一个被压缩到
06:45
to half the square area of Manhattan.
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曼哈顿一半那么大的一个物体。
06:47
So we move this Earth very close --
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所以我们把这个地球移动到离黑洞接近的地方 –
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30 kilometers outside --
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30公里处 –
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and we notice it's perfectly fine orbiting around the black hole.
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我们注意到它沿着完美的轨道绕黑洞运行。
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There's a sort of myth
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有一些传言
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that black holes devour everything in the universe,
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说黑洞将吞噬宇宙中的一切，
06:58
but you actually have to get very close to fall in.
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但实际上你必须离得非常近才会真的掉进去。
07:01
But what's very impressive is that, from our vantage point,
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但令人印象深刻的是，从我们的角度来看，
07:04
we can always see the Earth.
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我们总能看到地球。
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It cannot hide behind the black hole.
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它无法躲在黑洞后面。
07:08
The light from the Earth, some of it falls in,
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从地球发出的光，一部分落入黑洞，
07:10
but some of it gets lensed around and brought back to us.
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但还有一部分被黑洞弯折后被我们看到。
07:13
So you can't hide anything behind a black hole.
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所以你不能在一个黑洞后面藏任何东西。
07:15
If this were Battlestar Galactica
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如果这是太空堡垒卡拉狄加中的剧情
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and you're fighting the Cylons,
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而你正和赛昂人战斗，
07:19
don't hide behind the black hole.
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不要躲在黑洞后面。
07:21
They can see you.
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它们可以看到你。
07:24
Now, our Sun will not collapse to a black hole --
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我们的太阳不会坍缩成一个黑洞；
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it's not massive enough --
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它的质量不够大，
07:28
but there are tens of thousands of black holes in our galaxy.
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但在我们的银河系中有数以万计的黑洞。
07:32
And if one were to eclipse the Milky Way,
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如果其中的一个在吞噬银河系，
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this is what it would look like.
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它看上去将会是这个样子。
07:37
We would see a shadow of that black hole
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我们将会看到一个黑洞的影子
07:40
against the hundred billion stars
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投在银河系中数千亿颗恒星
07:42
in the Milky Way Galaxy and its luminous dust lanes.
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以及恒星照亮的尘埃带上。
07:45
And if we were to fall towards this black hole,
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如果我们坠向这个黑洞，
07:48
we would see all of that light lensed around it,
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我们会看到光在黑洞周围被折射，
07:51
and we could even start to cross into that shadow
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我们甚至在开始进入这个阴影的时候
07:54
and really not notice that anything dramatic had happened.
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完全不会感觉到一些巨大的变化正悄然发生。
07:57
It would be bad if we tried to fire our rockets and get out of there
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如果我们试图启动火箭并离开那里，结果不会很好，
08:00
because we couldn't,
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因为我们不可能逃离，
08:02
anymore than light can escape.
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连光也不可能逃离。
08:04
But even though the black hole is dark from the outside,
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虽然黑洞从外面看是漆黑的，
08:07
it's not dark on the inside,
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但是在里面看并非如此，
08:09
because all of the light from the galaxy can fall in behind us.
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因为所有星系的光线都可以随着我们一起落入黑洞。
08:12
And even though, due to a relativistic effect known as time dilation,
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而且即便如此，由于相对论的时间膨胀效应，
08:16
our clocks would seem to slow down
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我们的时钟相比银河系的时间而言
08:19
relative to galactic time,
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似乎变慢了，
08:22
it would look as though the evolution of the galaxy
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这看起来就好像
08:25
had been sped up and shot at us,
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外面的星系在加速变化，
08:27
right before we were crushed to death by the black hole.
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就在我们自己被黑洞摧毁之前。
08:30
It would be like a near-death experience
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这就像体验濒临死亡的感觉，
08:32
where you see the light at the end of the tunnel,
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你看到了隧道尽头的光明，
08:34
but it's a total death experience.
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不过这可是一个完整的死亡体验。
08:36
(Laughter)
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（笑声）
08:38
And there's no way of telling anybody
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你没有办法告诉任何人
08:40
about the light at the end of the tunnel.
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你在隧道尽头看到了光明。
08:42
Now we've never seen a shadow like this of a black hole,
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到目前为止，我们从来没有见过这样一个黑洞留下的阴影，
08:45
but black holes can be heard,
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但黑洞可以被听到，
08:47
even if they're not seen.
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即使它们不能被看到。
08:49
Imagine now taking an astrophysically realistic situation --
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想象一下，在一个真实的天文学景象里 –
08:53
imagine two black holes that have lived a long life together.
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想象两个已经一起存在了很长时间的黑洞。
08:56
Maybe they started as stars
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也许它们以前是恒星
08:58
and collapsed to two black holes --
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之后坍缩成了两个黑洞 –
09:00
each one 10 times the mass of the Sun.
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每一个的质量都是太阳的10倍。
09:03
So now we're going to crush them down to 60 kilometers across.
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现在我们把它们压缩到60公里之内。
09:06
They can be spinning
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它们每秒可以
09:08
hundreds of times a second.
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旋转数百次。
09:10
At the end of their lives,
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在生命的尽头，
09:12
they're going around each other very near the speed of light.
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它们以光速彼此靠近。
09:15
So they're crossing thousands of kilometers
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在几分之一秒内
09:17
in a fraction of a second,
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就能穿越了数千公里。
09:19
and as they do so, they not only curve space,
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在这个过程中，它们不仅会使空间发生弯曲，
09:21
but they leave behind in their wake
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还会在身后的尾流中
09:23
a ringing of space,
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造成空间的振动，
09:25
an actual wave on space-time.
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一种真实存在的时空波。
09:27
Space squeezes and stretches
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黑洞在和宇宙
09:29
as it emanates out from these black holes
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发生撞击的时候
09:31
banging on the universe.
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使得空间发生挤压和拉伸。
09:33
And they travel out into the cosmos
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这些振动以光速
09:35
at the speed of light.
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在太空中传播。
09:37
This computer simulation
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这个计算机模拟是
09:39
is due to a relativity group at NASA Goddard.
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由国家航空航天局戈达德的相对论组完成的。
09:42
It took almost 30 years for anyone in the world to crack this problem.
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解决这个问题前后花了近30年的时间。
09:45
This was one of the groups.
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这是众多小组中的一个。
09:47
It shows two black holes in orbit around each other,
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它展示了两个黑洞围绕着对方转动，
09:49
again, with these helpfully painted curves.
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这些是想象中的曲线。
09:51
And if you can see -- it's kind of faint --
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正如你所看到的 – 可能有些模糊 –
09:54
but if you can see the red waves emanating out,
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你能看到由红色的波被发射出来，
09:57
those are the gravitational waves.
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这些就是引力波。
09:59
They're literally the sounds of space ringing,
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它们是实实在在的宇宙的声音，
10:02
and they will travel out from these black holes at the speed of light
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这些声音将在黑洞相互融合的过程中
10:04
as they ring down and coalesce
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以光速从这些黑洞向外传播，
10:07
to one spinning, quiet black hole
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直到这两个黑洞融为一体
10:09
at the end of the day.
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成为一个安静地旋转着的黑洞。
10:11
If you were standing near enough,
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如果你站得足够近，
10:13
your ear would resonate
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你的耳朵会与
10:15
with the squeezing and stretching of space.
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这些空间的挤压和拉伸产生共鸣。
10:17
You would literally hear the sound.
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你真的能够亲耳听到这些声音。
10:19
Now of course, your head would be squeezed and stretched unhelpfully,
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当然，你会无助地发现你的头也被挤压和拉伸，
10:23
so you might have trouble understanding what's going on.
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所以你可能无法理解究竟发生了什么。
10:26
But I'd like to play for you
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不过我愿意为你们播放一下
10:28
the sound that we predict.
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我们预测的声音。
10:30
This is from my group --
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这是我的小组的研究成果 -
10:32
a slightly less glamorous computer modeling.
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一个相对简略的计算模型。
10:35
Imagine a lighter black hole
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想象一个质量较小的黑洞
10:37
falling into a very heavy black hole.
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落入一个质量较大的黑洞。
10:39
The sound you're hearing
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你听到的声音
10:41
is the light black hole banging on space
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来自小质量黑洞在靠近大质量黑洞的过程中
10:44
each time it gets close.
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与空间发生的碰撞。
10:46
If it gets far away, it's a little too quiet.
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如果它们距离很远，声音会非常小。
10:49
But it comes in like a mallet,
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但渐渐的声音变得像一个鼓槌
10:51
and it literally cracks space,
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敲打着空间，
10:53
wobbling it like a drum.
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让空间像鼓一样发生振动。
10:55
And we can predict what the sound will be.
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我们可以预测这个声音会变成什么样。
10:58
We know that, as it falls in,
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我们知道，在坠落的过程中，
11:00
it gets faster and it gets louder.
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小质量黑洞会越来越快，发出的声音也更响亮。
11:02
And eventually,
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最终，
11:04
we're going to hear the little guy just fall into the bigger guy.
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我们将听到小黑洞完全掉进了大黑洞。
11:07
(Thumping)
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（咚）
11:24
Then it's gone.
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它们不见了。
11:26
Now I've never heard it that loud -- it's actually more dramatic.
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我从来没觉得这声音有这么响 - 在这儿它实际上被放大了。
11:28
At home it sounds kind of anticlimactic.
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在家里听的时候，觉得这声音有些不给力。
11:30
It's sort of like ding, ding, ding.
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听起来就像，叮，叮，叮。
11:32
This is another sound from my group.
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这是我们研究小组模拟的另一个声音。
11:36
No, I'm not showing you any images,
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我在这儿并不会给大家展示图像，
11:38
because black holes don't leave behind
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因为黑洞不会留下
11:40
helpful trails of ink,
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任何有用的踪迹，
11:42
and space is not painted,
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真正的空间也不会向你展示
11:44
showing you the curves.
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那些虚拟的曲线。
11:46
But if you were to float by in space on a space holiday
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不过如果你在宇宙中度假的时候
11:48
and you heard this,
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听到这个声音，
11:50
you want to get moving.
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我建议你赶快跑。
11:52
(Laughter)
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（笑）
11:54
Want to get away from the sound.
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最好赶快远离这声音。
11:56
Both black holes are moving.
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这两个黑洞都在移动。
11:58
Both black holes are getting closer together.
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两个黑洞在向彼此靠近。
12:01
In this case, they're both wobbling quite a lot.
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在这种情况下，它们都在猛烈地摇晃。
12:04
And then they're going to merge.
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然后，它们将融为一体。
12:06
(Thumping)
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（咚）
12:14
Now it's gone.
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它们不见了。
12:16
Now that chirp is very characteristic of black holes merging --
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那个尖锐的声音是黑洞融合的标志 -
12:19
that it chirps up at the end.
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融合结束的时候就会发出尖锐的响声。
12:22
Now that's our prediction
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这是我们对我们将会看到的东西
12:24
for what we'll see.
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所做出的预测。
12:26
Luckily we're at this safe distance in Long Beach, California.
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幸运的是我们在加州长滩非常安全。
12:28
And surely, somewhere in the universe
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毋庸置疑，在宇宙的某个地方两个黑洞
12:30
two black holes have merged.
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已经融合在一起。
12:32
And surely, the space around us
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同样毋庸置疑的是，我们周围的空间
12:34
is ringing
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也能感受到这些穿越一百万光年的，
12:36
after traveling maybe a million light years, or a million years,
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或者说来自一百万年前的振动，
12:39
at the speed of light to get to us.
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它们以光速传播并最终与我们相遇。
12:42
But the sound is too quiet for any of us to ever hear.
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但这些声音太小，以至于我们根本听不到。
12:45
There are very industrious experiments being built on Earth --
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世界上有些实验需要耗费很多心血才能搭建起来 –
12:48
one called LIGO --
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其中有一个叫LIGO的的实验 -
12:50
which will detect deviations
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它将能检测到
12:52
in the squeezing and stretching of space
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每四公里的距离上
12:55
at less than the fraction of a nucleus of an atom
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小于一个原子核范围的
12:58
over four kilometers.
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空间振动。
13:00
It's a remarkably ambitious experiment,
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这是一个非常大胆的尝试，
13:02
and it's going to be at advanced sensitivity
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它的灵敏度在未来几年里
13:04
within the next few years -- to pick this up.
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将不会被超越 - 它将用来检测空间振动。
13:07
There's also a mission proposed for space,
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另外一个关于宇宙的研究项目
13:09
which hopefully will launch in the next ten years,
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有望在未来十年内启动，
13:11
called LISA.
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这个项目叫LISA。
13:13
And LISA will be able to see super-massive black holes --
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LISA将可以看到超大质量的黑洞 -
13:16
black holes millions or billions of times
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那些质量是太阳的
13:19
the mass of the Sun.
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几百万倍甚至几十亿倍的黑洞。
13:21
In this Hubble image, we see two galaxies.
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从哈勃望远镜传回的图像里，我们看到这两个星系。
13:24
They look like they're frozen in some embrace.
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看起来它们像是静止地拥抱在一起。
13:27
And each one probably harbors
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它们的中心可能分别存在着
13:29
a super-massive black hole at its core.
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一个质量巨大的超级黑洞。
13:32
But they're not frozen;
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但它们并非静止不动，
13:34
they're actually merging.
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实际上它们正在融合。
13:36
These two black holes are colliding,
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这两个黑洞将发生碰撞，
13:38
and they will merge over a billion-year time scale.
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它们的融合将经历数十亿年的时间。
13:41
It's beyond our human perception
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因此搜集它们发出的声音
13:43
to pick up a song of that duration.
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已经超出了我们人类的感知极限。
13:46
But LISA could see the final stages
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但LISA可以看到
13:48
of two super-massive black holes
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两个在很早之前就开始
13:50
earlier in the universe's history,
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发生融合的超大质量黑洞的最后阶段，
13:52
the last 15 minutes before they fall together.
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也就是它们融合前的15分钟。
13:55
And it's not just black holes,
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这种探测并不只限于黑洞，
13:57
but it's also any big disturbance in the universe --
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它还能用来探测宇宙中任何大的扰动 -
14:00
and the biggest of them all is the Big Bang.
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其中最大的扰动要数“宇宙大爆炸”了。
14:02
When that expression was coined, it was derisive --
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当这个词语被创造出来的时候，有些人嘲弄说 -
14:05
like, "Oh, who would believe in a Big Bang?"
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“噢，谁会相信宇宙大爆炸？”
14:07
But now it actually might be more technically accurate
336
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但现在看来这个词语其实从字面上来看可能是非常准确的，
14:09
because it might bang.
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因为它确实可能爆炸;
14:11
It might make a sound.
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发出砰的一声。
14:13
This animation from my friends at Proton Studios
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这个有我在Proton Studios的朋友制作的动画短片
14:16
shows looking at the Big Bang from the outside.
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展示了从外部观看大爆炸的情景。
14:18
We don't ever want to do that actually. We want to be inside the universe
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我们其实绝不会愿意真的这样；我们希望置身于宇宙的内部，
14:21
because there's no such thing as standing outside the universe.
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因为根本不存在置身宇宙之外这样的情况。
14:24
So imagine you're inside the Big Bang.
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所以，想象一下你置身于大爆炸之中。
14:26
It's everywhere, it's all around you,
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宇宙无处不在，世间万物都环绕在你的周围，
14:28
and the space is wobbling chaotically.
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空间在无序地摇摆。
14:30
Fourteen billion years pass
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140亿年过去了，
14:32
and this song is still ringing all around us.
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而这声音依然萦绕在我们身边。
14:35
Galaxies form,
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星系逐渐形成，
14:37
and generations of stars form in those galaxies,
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一批一批的恒星在星系中形成。
14:39
and around one star,
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在某个星球上，
14:41
at least one star,
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至少存在一个这样的星球，
14:43
is a habitable planet.
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适合生命居住。
14:45
And here we are frantically building these experiments,
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在这里，我们疯狂地搭建实验，
14:48
doing these calculations, writing these computer codes.
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做计算，写计算机代码。
14:50
Imagine a billion years ago,
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想象一下，十亿年前，
14:53
two black holes collided.
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两个黑洞相撞。
14:55
That song has been ringing through space
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这声音一直以来
14:57
for all that time.
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都在时空中穿梭。
14:59
We weren't even here.
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我们甚至都没出现在这里。
15:01
It gets closer and closer --
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它越来越近 -
15:03
40,000 years ago, we're still doing cave paintings.
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40,000年前，我们还在洞穴的石壁上画画。
15:05
It's like hurry, build your instruments.
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画上的人仿佛在说“快，把仪器搭建起来。”
15:07
It's getting closer and closer, and in 20 ...
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时间进一步推进，
15:10
whatever year it will be
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在20XX年...未来的某一年
15:12
when our detectors are finally at advanced sensitivity --
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我们终于拥有了高灵敏度的先进探测器 -
15:14
we'll build them, we'll turn on the machines
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我们建造这些探测器，打开开关，
15:16
and, bang, we'll catch it -- the first song from space.
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砰，我们捕捉到了这个声音 - 来自太空的第一首歌曲。
15:19
If it was the Big Bang we were going to pick up,
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如果我们所要获取的声音是宇宙大爆炸发出的，
15:21
it would sound like this.
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它听起来会像这样。
15:23
(Static) It's a terrible sound.
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（抨击声）这声音真难听。
15:26
It's literally the definition of noise.
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严格地讲，它就是噪声。
15:28
It's white noise; it's such a chaotic ringing.
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这是一种白噪声，一种混乱的铃声。
15:30
But it's around us everywhere, presumably,
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但它在我们周围无处不在，
15:33
if it hasn't been wiped out
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只要它没有被宇宙中的
15:35
by some other process in the universe.
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某些其他过程所抵消的话。
15:37
And if we pick it up, it will be music to our ears
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如果我们能够探测到这些声音，对我们的耳朵来说这将像音乐一般，
15:40
because it will be the quiet echo
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因为这安静的回声
15:42
of that moment of our creation,
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来自于我们被创造的瞬间，
15:44
of our observable universe.
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来自于我们抬头遥望的宇宙。
15:46
So within the next few years,
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因此在未来的几年里，
15:48
we'll be able to turn up the soundtrack a little bit,
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我们将能把这些配乐的音量调大一点点，
15:51
render the universe in audio.
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让宇宙以音频的形式呈现给我们。
15:54
But if we detect those earliest moments,
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但是，如果我们能够探测到那些最早的瞬间，
15:57
it'll bring us that much closer
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它还将使我们
15:59
to an understanding of the Big Bang,
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离理解大爆炸更进一步，
16:01
which brings us that much closer
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使我们能够去追问一些最为困难，
16:04
to asking some of the hardest, most elusive, questions.
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同时也最为飘渺的问题。
16:07
If we run the movie of our universe backwards,
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如果我们倒着播放宇宙的历程，
16:10
we know that there was a Big Bang in our past,
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我们可以知道过去曾有过一次大爆炸，
16:13
and we might even hear the cacophonous sound of it,
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我们甚至可以听到它那吵杂的声音，
16:17
but was our Big Bang the only Big Bang?
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但我们的大爆炸是宇宙中唯一的大爆炸吗？
16:19
I mean we have to ask, has it happened before?
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我的意思是我们不禁会问，在那之前有没有发生过类似的大爆炸呢？
16:22
Will it happen again?
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将来会不会再次发生呢？
16:24
I mean, in the spirit of rising to TED's challenge
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我想说如果把这个问题的意义上升到
16:27
to reignite wonder,
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TED所倡导的引发人们重新思考的这个层面，
16:29
we can ask questions, at least for this last minute,
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至少在这最后一分钟里，我们可以提出一些问题，
16:32
that honestly might evade us forever.
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那些我们确实可能永远也回答不了的问题。
16:34
But we have to ask:
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但我们不禁要问：
16:36
Is it possible that our universe
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我们的宇宙会不会
16:38
is just a plume off of some greater history?
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只是一部更宏大的历史中的一段插曲？
16:41
Or, is it possible that we're just a branch off of a multiverse --
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又或者说，我们会不会只是多元宇宙中的一个分支 –
16:45
each branch with its own Big Bang in its past --
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每个分支都曾经历过自己的大爆炸 –
16:49
maybe some of them with black holes playing drums,
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也许它们中的一些存在嗡嗡作响的黑洞，
16:51
maybe some without --
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也许有些没有 –
16:53
maybe some with sentient life, and maybe some without --
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也许一些存在有意识的生命，也许有些不存在 –
16:56
not in our past, not in our future,
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它们不属于我们的过去，也不存在于我们的未来，
16:58
but somehow fundamentally connected to us?
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而是以某种方式与我们联系在一起？
17:01
So we have to wonder, if there is a multiverse,
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因此，我们忍不住会猜测，如果存在一个多元宇宙，
17:03
in some other patch of that multiverse,
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在这个多元宇宙中的其他分支中，
17:05
are there creatures?
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存在生命吗？
17:07
Here's my multiverse creatures.
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这是我们这个多元宇宙中生命。
17:09
Are there other creatures in the multiverse,
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多元宇宙中是否还有其他生命，
17:11
wondering about us
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他们会不会也在猜测我们的存在，
17:13
and wondering about their own origins?
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思考着他们自己的起源？
17:16
And if they are,
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如果是这样的，
17:18
I can imagine them as we are,
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我能想象他们与我们一样，
17:21
calculating, writing computer code,
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做计算，编写计算机代码，
17:23
building instruments,
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搭建实验仪器，
17:25
trying to detect that faintest sound
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试图探测那些
17:28
of their origins
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来自于他们起源时的微弱声音，
17:30
and wondering who else is out there.
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并怀疑还有谁在那里。
17:32
Thank you. Thank you.
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谢谢。谢谢大家。
17:35
(Applause)
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（掌声）
ABOUT THE SPEAKER
Janna Levin - PhysicistJanna Levin is a professor of physics and astronomy at Barnard, where she studies the early universe, chaos, and black holes. She's the author of “How the Universe Got Its Spots" and the novel “A Madman Dreams of Turing Machines.”
Why you should listen
Janna Levin is a Professor of Physics and Astronomy at Barnard College of Columbia University. Her scientific research concerns the early universe, chaos and black holes. Her second book – a novel, A Madman Dreams of Turing Machines – won the PEN/Bingham Fellowship for Writers and was a runner-up for the PEN/Hemingway award for "a distinguished book of first fiction." She is the author of the popular science book, How the Universe Got Its Spots: Diary of a Finite Time in a Finite Space.
She holds a BA in Physics and Astronomy from Barnard College with a concentration in Philosophy, and a PhD from MIT in Physics. She has worked at the Center for Particle Astrophysics (CfPA) at the University of California, Berkeley before moving to the UK where she worked at Cambridge University in the Department of Applied Mathematics and Theoretical Physics (DAMTP). Just before returning to New York, she was the first scientist-in-residence at the Ruskin School of Fine Art and Drawing at Oxford with an award from the National Endowment for Science, Technology, and Arts (NESTA).
Listen to a Q&A with another TED speaker, Krista Tippett -- where they talk math and faith and truth and more ...
Janna Levin | Speaker | TED.com