The sound the universe makes | Janna Levin

196,962 views ・ 2011-03-15

TED


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翻译人员: Chen Huang 校对人员: Angelia King
00:15
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
01:54
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。
02:23
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
03:50
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,
03:59
you would make a black hole,
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你将制造出一个黑洞,
04:01
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,
04:09
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,
04:11
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–
04:15
joined the German army already an accomplished scientist,
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他加入德军,在俄国前线工作,
04:18
working on the Russian front.
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那时已经是位非常杰出的科学家了。
04:21
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
04:24
calculating ballistic trajectories for cannon fire,
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计算着加农炮的弹道轨迹,
04:28
and then, in between,
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然后再时不时地,
04:30
calculating Einstein's equations --
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算算爱因斯坦方程–
04:32
as you do in the trenches.
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试想一下那是什么样的一个情景。
04:34
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
04:36
general theory of relativity,
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广义相对论,
04:38
and he was thrilled by this theory.
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他被这个理论震惊了。
04:40
And he quickly surmised
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并且很快推导出
04:42
an exact mathematical solution
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一个精确的数学解
04:44
that described something very extraordinary:
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描述了一个非常异常的结果:
04:46
curves so strong
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如果弯折过于强烈
04:48
that space would rain down into them,
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宇宙将向内部塌陷,
04:51
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。
04:55
And even light could not escape this current.
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光甚至都不能逃脱这股暗流。
04:58
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,
05:02
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。
05:04
Now he wrote to Einstein,
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他写信给爱因斯坦,
05:06
and he said, "As you will see,
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他说:“正如你将看到的,
05:08
the war has been kind to me enough.
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战争对我还是挺仁慈的,
05:11
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。
05:25
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。
05:28
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。
05:36
He did not believe they existed in nature.
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他并不相信真的存在黑洞。
05:39
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。
05:42
It was decades
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人们在数十年之后
05:44
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
05:48
that black holes are real astrophysical objects --
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黑洞是真实存在的天体 –
05:50
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
05:54
that collapse catastrophically
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发生灾难性坍缩后的
05:56
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。
06:00
It's actually not massive enough.
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它的质量其实不足够大。
06:02
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 –
06:04
as Einstein was very fond of doing --
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爱因斯坦非常喜欢这样做 –
06:06
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
06:35
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。
06:37
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。
06:43
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 –
06:49
30 kilometers outside --
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30公里处 –
06:51
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。
06:54
There's a sort of myth
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有一些传言
06:56
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。
07:06
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
07:17
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;
07:26
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,
07:35
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.
347
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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.
354
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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
357
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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.
361
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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 --
365
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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)
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