了解宇宙是如何运行的（2010）

How the Universe Works S09E08

Part 6 March 16, 2022, 8:55 a.m.

他们通过研究中微子和它们的对称孪生
They re-created part of
the Big Bang by
反♥中♥微子
studying neutrinos
重新创造了大爆♥炸♥的一部分
and their symmetrical twin,
antineutrinos.
目标是——看看反♥中♥微子是否
The goal -- to see if
antineutrinos change their
以与普通中微子相同的速度改变它们的特性或味道
identity or flavor at the same
rate as regular neutrinos.
物质和反物质的行为0应该是完全相同的
Matter and antimatter should
behave exactly the same,
但是我们在这个实验中发现了一些
but we found something very
interesting with
非常有趣的事情
this experiment.
粒子打破了对称性
The particles broke symmetry.
中微子和反♥中♥微子以不同的速率
Neutrinos and antineutrinos
changed flavor at
改变味道
different rates.
这是物质与反物质行为
This was a clear-cut example
不同的一个明确的例子
of matter behaving differently
than antimatter.
这彻底改变了我们
<其实这就是杨振宁的“宇称不守恒定律”>
<并由吴健雄第一个用巧妙的实验验证>
<相关信息可以问度娘——译者注>
And that has
revolutionized our understanding
对大爆♥炸♥中粒子形成的理解
<其实这就是杨振宁的“宇称不守恒定律”>
<并由吴健雄第一个用巧妙的实验验证>
<相关信息可以问度娘——译者注>
of the formation of particles
during the Big Bang.
奥卢塞伊:在早期宇宙中可能发生的情况是
<其实这就是杨振宁的“宇称不守恒定律”>
<并由吴健雄第一个用巧妙的实验验证>
<相关信息可以问度娘——译者注>
OLUSEYI: What could have
happened in the early universe
转化成物质的中微子数量
<其实这就是杨振宁的“宇称不守恒定律”>
<并由吴健雄第一个用巧妙的实验验证>
<相关信息可以问度娘——译者注>
is that more of the neutrinos
converted into matter
多于转化成反物质的反♥中♥微子数量
<其实这就是杨振宁的“宇称不守恒定律”>
<并由吴健雄第一个用巧妙的实验验证>
<相关信息可以问度娘——译者注>
than there were antineutrinos
became into antimatter,
通过这种方式，你最终会得到
and in this way, you end up
with a surplus of matter
多余的物质
over antimatter.
即使这些剩余的粒子
Even though
that surplus was just
只有十亿分之一
one particle in a billion,
也足以构建宇宙
it was enough to build
the cosmos.
奥卢瑟伊:所以早期宇宙中的中微子
OLUSEYI: So neutrinos
in the early universe
可能解决我们所面临的
could possibly solve the matter,
正反物质不对称问题
antimatter asymmetry problem
we have.
是的，它们会造成破坏
Yes, they cause destruction.
它们，你懂的，有时候它们会炸掉一颗恒星
They -- you know, sometimes
they blow up a star,
但最终，他们确实拯救了
but, at the end of the day,
they did save
整个宇宙
the entire universe.
现在，科学家们希望中微子
Now, scientists hope
that neutrinos may solve
能够解开宇宙中最大的谜团之一——
one of the biggest mysteries
in the cosmos --
暗物质的身份
The identity of dark matter.
自宇宙诞生以来
Neutrinos have
been around since
中微子就一直存在
the birth of the universe.
它们甚至可能是物质形成的原因
They may even be responsible
for the formation of matter.
现在我们研究它们是否在宇宙的发展
Now we investigate
if they play an even
宇宙网的形成中发挥了
larger role in the development
of the universe,
更大的作用
the formation of the cosmic web.
在我们宇宙中最大的尺度上
At the very largest
scales in our universe,
星系以一种非常奇特的模式排列
galaxies are arranged in
a very peculiar pattern.
我们看到了细长的星系线
We see long, thin threads
of galaxies,
在交叉处，我们看到了稠密的
and at the intersections, we
see dense clumps of galaxies
星系团
called clusters.
在它们之间，有一些
In between them,
we have these vast
巨大的空洞区域，称为宇宙空洞
empty regions called
the cosmic voids.
很长一段时间，宇宙网
For a long time,
how the cosmic
是如何形成并维系在一起的还是一个谜
web formed and held together
was a mystery.
关于我们的存在，一个真正的谜团是
One of the real mysteries
about our existence is
为什么宇宙能够保持完整
why the universe was able to
hold together at all.
所有的物质只是分散开来
All the matter was simply
spread apart
稀疏地形成星系或恒星
to sparsely to ever form
galaxies or stars.
相反，有什么东西帮助它团结在一起
Instead, something helped
to hold it together.
我们现在认为，连接宇宙网的粘合剂
We now think
the glue binding the cosmic web
是一种被称为暗物质的神秘物质
is a mysterious substance
known as dark matter.
如果宇宙早期没有暗物质
If it wasn't for dark matter
in the very early universe,
可能根本就没有结构
there might be no structure
at all.
但是这个宇宙的建筑师是什么
But what is this
architect of the universe,
暗物质吗？
this dark matter?
埃斯基夫:暗物质是我们看不见的无形物质——
ESQUIVE: Dark matter is
invisible matter that we can't
所以你，我，所有的粒子，我们所看到的
see -- so you, me, all of
the particles, everything that
一切物质实际上只占宇宙中实际物质的5%
we see is actually only 5% of
actual matter in the universe.
剩下的是暗物质
<还有暗能量——译者注>
The rest is dark matter.
特马克:暗物质是我们对不了解的东西
TEGMARK:
Dark matter is a fancy name
起的一个花哨的名字
for something
we don't understand.
我们所知道的是
What we do know is that there
宇宙中有很多我们看不到的东西
is much more stuff
than we can see.
但我们不知道它是什么
But we have no idea what it is.
这是科学界最大的未解之谜之一
It's one of the greatest
open mysteries in science.
暗物质几乎不与任何东西相互作用
Dark matter hardly
interacts with anything,
有点像中微子——同样和中微子一样
a bit like neutrinos --
Also like neutrinos,
暗物质在早期的宇宙中丰富而活跃
dark matter was abundant and
active in the infant universe.
那么中微子和暗物质可能是一回事吗？
So could neutrinos and dark
matter be the same thing?
普莱特:我们不知道暗物质是什么
PLAIT: We don't know
what dark matter is,
但我们知道它的行为方式
but we kind of know
how it behaves.
中微子听起来是一个很好的候选者
And neutrinos sound like
a pretty good candidate for it
因为，嘿，它们很暗
because, hey, they are dark.
它们在宇宙中无处不在
They are everywhere
in the universe,
它们确实有点质量
and they do have a little bit
of mess.
说到一点点，我们确实是指一点点——
And by little,
we do mean little -- neutrinos
中微子的重量大约是一粒沙子的
weigh around 10 billion,
billion, billion
100亿亿亿亿分之一
times less than a grain of sand.
但中微子也是非常丰富的
But neutrinos are also
exquisitely abundant, and so
正因为它们如此丰富
because they're so abundant,
所以个体微小的它们实际上可以在非常大的尺度上
their individual tiny mass can
actually add up to a large
叠加成一个巨大的弥散质量
diffuse mass
on very large scales.
为了研究中微子
To investigate
和暗物质是否相同
if neutrinos and dark matter
are the same thing,
我们必须回到宇宙大爆♥炸♥
we must return to the Big Bang.