与摩根·弗里曼一起穿越虫洞（2010）

Through The Wormhole With Morgan Freeman S05E09

Part 3 April 19, 2021, 3:04 p.m.

右旋中微子
The right-handed neutrino
如此难以捉摸
would be too elusive to be detected
以至于现有的地下暗物质检测设备都无法检测到
in current underground dark matter searches.
不过，安德烈认为
However, André believes
我们可能有另一种方式找到右旋中微子——向天上看
there might be another way to find it -- by looking up.
右旋中微子并不稳定
Right-handed neutrinos are not completely stable.
就像放射性元素一样会衰变
Like radioactive elements, they sometimes fall apart,
右旋中微子衰变时会产生X射线
and as they do, they create a flash of X-ray light.
右旋中微子有一个非常重要的特征
A very important feature about right-handed neutrinos,
它会放出X射线
is that they came to X-rays.
那么寻找
So one way to look for
像右旋中微子这样的暗物质
right-handed neutrinos as dark matter
就要观察天空的某个区域
is to look at a region of the sky,
看这些区域是否会释放X射线
and we see if these galaxies are emitting X-rays.
近期对于遥远的星系的研究
In fact, recent studies of distant galaxies
已经发现了释放X射线的
have detected some strange anomalies
异常区域
in the X-rays they emit.
这些异常区域也许指明了
These anomalies might signal the border
光明世界与黑暗宇宙的界线
between the world of light and the shadows.
那么黑暗之中都发生着什么？
What's happening in that darkness?
有些天文学家认为他们已经发现了
Some astronomers believe they have found evidence
复杂暗物质宇宙存在的证据
of a complex shadow universe...
那些幽灵般的物质就在我们身边
...where ghostly substances coalesce all around us,
甚至就在我们体内
even inside us.
宇宙中
Out in the cosmos,
两块暗物质正向着彼此方向运动
two masses of dark matter are moving toward one another.
当它们碰撞时会发生什么？
what happens when they collide?
大多科学家会说，什么也不会发生
Most scientists would say almost nothing.
暗物质似乎只具有微弱的引力作用
dark matter appears to feel only the weak force of gravity,
但他们可能过于简化了暗物质
But they may have oversimplified how dark matter behaves.
也许暗物质宇宙
Perhaps this shadow universe
是由更复杂的物质构成的
is made of more complicated material.
在威尔·道森成为天体物理学家之前
Before will dawson became an astrophysicist,
他是一位近海结构工程师
he was an offshore structural engineer,
如今他决定脱下手套和安全帽
but he decided to take off his gloves and hard hat
追随自己对暗物质的热情
to follow his passion for dark matter.
这还是在他玩蹦床时做的决定
It was a decision that has him jumping for joy.
威尔是寻找暗物质蛛丝马迹的
Will is one of the lucky scientists
幸运的科学家之一
who has seen dark matter's telltale fingerprints,
他发现了暗物质的引力效应
its gravitational effects.
我们面对的主要挑战之一
So one of the major challenges that we face is
就是如何在看不见暗物质的情况下
how exactly do you measure where dark matter is
对它进行测量，暗物质并不会发光
if you can't see it? It doesn't emit light.
我们使用的技术称之为引力透镜
So what we use is a technique called gravitational lensing,
这里的基本原理
and the basic principle behind this
就是在正常情况下
is that under a normal circumstance,
比如平滑的时空
a flat space-time,
光就沿直线传播
light always travels in straight lines.
不过，当你在平滑时空中引入了有质量的物体
However, when you introduce a mass to this space-time,
时空就会发生扭曲
this space-time gets curved and distorted,
光则随着空间的弯曲程度发生弯曲
and light actually follows the curvature of that space.
这种由于质量导致的光路弯曲
This gravitational distortion of light by mass
就可以让像威尔这样的天文学家
allows astronomers like will
找到巨型暗物质团的位置
to find the position of giant cosmic clouds of dark matter.
他们拍摄了多个遥远星系的图像
They look for double images of more distant galaxies
这些星系的光芒在暗物质团周围发生了弯曲
whose light is being bent around either side of the clouds.
有两团特定的暗物质
Two particular clouds of dark matter
引起了威尔的主意
caught will's attention.
这两团暗物质分别是两个子弹星团的一部分
The clouds were part of the bullet cluster,
这两个星团在距离地球
a collision of two galaxy clusters
几十亿光年远的地方发生了碰撞
a few billion light-years from earth.
每个星系团
Each galaxy cluster
都由成百上千个星系组成
is composed of hundreds or thousands of galaxies.
当这两个宇宙巨物发生碰撞时
When these two cosmic giants collided...
其中的星系会径直穿过
...the galaxies themselves moved right past one another
因为每个星系间都相距几百万光年远
because they were millions of light-years apart.
但其中弥散的氢氦气体团
But the diffuse clouds of hydrogen and helium gas
会互相摩擦碰撞
surrounding the galaxies barreled right into one another.
电磁力使得
The force of electromagnetism
其中的原子发生爆♥炸♥，使得星团变成子弹形状的地狱
caused their atoms to explode into a bullet-shaped inferno,
但暗物质团却不受影响
but the dark matter clouds were unfazed by all this.
它们毫无阻碍的穿过对方
They sailed right through one another.
它们也不会向常规物质那样
They didn't feel the powerful force of electromagnetism
受到电磁力的影响
that regular matter feels,
唯一发挥作用的就是那极弱的引力
only the incredibly weak force of gravity.
威尔在想宇宙中为什么有这么多奇特物质
Will wondered why such a huge portion of our universe
能够丝毫不受周遭环境的影响
would be so oblivious to what is happening all around it.
暗物质真的仅是一些惰性物质吗？
Is dark matter really just dumb matter?
我们知道它可以通过引力与其他物质相互作用
We know that it interacts via gravity,
那么问题来了
and now the question is,
暗物质会有更多作用吗？
is dark matter more interesting than that?
暗物质宇宙会比乍一看
Is the dark universe much more complex
还要复杂吗？
than it is at first sight?
威尔组织了一个团队
Will formed a collaboration to find out
他们想要知道关于子弹星团碰撞的说明
if the accepted interpretation of the bullet cluster collision
是否过度简化了暗物质的功能
oversimplified what dark matter does.
这个星团中
Is this the cluster
是否含有暗物质呢？
that has the dark matter in the middle or no?
呃，是有暗物质的
Uh, it has dark matter in middle,
但这并不像
but it's not the same thing that...
这个团队正在观测
the group is looking at many more
更多的互相碰撞的星系团
colliding galaxy clusters.
他们想知道暗物质
They want to see if dark matter
是否会直接穿过对方
always passes right through itself
并仍处于原来的星团之中
and stays lined up with its original galaxies.
我们想要做的就是
And so what we're trying to do is measure
测量星系及暗物质之间
whether there's an offset between the galaxies
是否存在阻碍
and the dark matter.
如果我们观察到了阻碍
If we observe an offset,
这就可以证明
then that's clear evidence
暗物质之间会有相互作用
that dark matter is interacting with itself.
有一个星团
There was one galaxy cluster
引起了他们的注意
that had their attention.
它类似子弹星团，但更古老、移♥动♥更慢
It was like the bullet cluster but older and slower.
他们就称它为“火枪子弹”
So they called it the musket ball.
火枪子弹星团更早的
The musket ball cluster is much further progressed
进入了融合期
in its merger phase.
在这个星团里你能看到
The bullet cluster you almost see right after
这里面是两个刚刚穿过对方的星团
the two clusters have passed through one another,
不过整个火枪子弹星团还要一段时间才能分开
whereas the musket ball cluster has had more time to separate.
就像这盘子里的意大利菜一样，有酱
Just as a plate of italian food has sauce,
有肉丸，还有意大利面
meatballs, and pasta,
一个星团里面有气体物质
a galaxy cluster has gas...
很多星系
galaxies...
还有暗物质
and dark matter.
星团碰撞就像用餐时的分歧
And just as theoretical disagreements
会被激化
over a meal can get heated,
星团中的各种成分也会变得
ingredients in a galaxy cluster have a tendency to get...
更加混乱
a little messy.
就像我们刚才的战斗
A galaxy cluster is a lot like our food fight we just had.
星团碰撞会变得很混乱
Not only are these galaxy clusters mergers very messy,
星团中的星系之间有很多空间
but the galaxies -- there's just so much space in between them.
它们就像肉丸
They're a lot like the meatballs
两边直接穿了过去
that -- that just pass right on through.
而气体物质，就像意大利酱一样
The gas, however, is a lot like the sauce,
只要我们泼出去
which, whenever we threw it,
它们就会发生碰撞
a lot of it collided and got stuck in the middle.
而暗物质
And the dark matter --
就有点像意大利面
it's a little bit like the pasta that we were dealing with,
大多数意大利面都从对方的间隙中穿了过去
where most of the pasta misses one another.