了解宇宙是如何运行的（2010）

How the Universe Works S08E07

Part 4 Jan. 30, 2022, 2:58 p.m.

……但天文学家认为
...But astronomers believe
这还不是宇宙的全部
this isn't the full extent
of the universe.
我们不知道的是宇宙中有多少
What we don't know is how much
of the universe
是我们可观测的宇宙
is our observable universe.
它可能只是这个浩瀚宇宙中的一个微小的
It could be a tiny,
microscopic speck of this
微观的小点
much more vast universe.
我们只是不知道
We just don't know.
卡罗尔:我们不知道在可观测宇宙之外
Carroll: We have no idea
how much stuff there is
有多少物质
outside the observable universe,
但因为从定义上讲，它在可观测宇宙之外
but because by definition, it's
outside the observable universe,
我们现在真的不知道
we really don't know right now.
那么那里有什么呢？
Narrator:
So what is out there?
有一种理论认为，可观测宇宙之外的空间
One theory says that space
outside the observable universe
与我们所在的宇宙附近的空间几乎是一样的
is pretty much the same
as our own cosmic neighborhood.
它更大的宇宙就像这里一样
It's just more universe.
It's just like here.
它刚好够远，我们看不到它
It's just far enough away
that we can't see it.
所以没有什么奇怪的地方可以让时间倒流
So it's not like there's bizarre
places where time runs backwards
或者外星人有两个脑袋，嗯，是的，也许吧
or aliens have two heads,
well, yeah, maybe.
但是在更遥远的
Narrator: But further out
更宽广的宇宙深处
in the deepest parts
of the greater universe,
事情就难说了
all bets are off.
我们预计，当你到达可观测宇宙的
We expect that as you go sort of
twice or three times
两到三倍时
beyond the observable universe,
它可能和我们居住的宇宙非常相似
it's probably very similar
to the universe we inhabit.
但如果你到一千倍或一百万倍远
But if you go a thousand times
or a million times farther,
谁知道你会看到什么？
who knows what you might see?
如果我们走得够远，情况可能会非常非常不同
It might be very, very different
if we go far enough away.
奇怪的是，这一切都回到了
Narrator: Strangely,
it all comes back
宇宙的膨胀
to the expansion of the universe
以及这个过程中的一个关键细节
and one crucial detail
in that process.
在宇宙早期的历史中
There was a brief moment
有一个短暂的时刻
in the very early history
of the universe
它的膨胀速度非常快
where its expansion
accelerated hugely.
这种加速被称为暴胀
This acceleration
is called inflation,
在很短的时间内，宇宙本身
and in a brief moment,
the universe itself expanded
以数倍于光速的速度膨胀
at multiple times
the speed of light.
暴胀是我们宇宙形成的
Narrator: Inflation was
a formative moment
一个阶段
for our universe.
当它停止的时候
By the time it stopped,
宇宙的基本特征已经形成
the universe's basic
characteristics were set.
这些基本常数
There are these
fundamental constants
描述了我们宇宙中的现象
that describe the phenomena
in our universe,
物质、光和时空的基本原理
the fundamentals of matter
and light and space-time.
但是一些科学家认为
Narrator:
But some scientists think
在更大的宇宙中
there could be regions
of the greater universe
可能有一些区域的暴胀从未停止过
where inflation
has never stopped.
这个观点认为，更大的宇宙正在以疯狂的速度膨胀
The idea is the greater universe
is expanding at an insane speed,
但偶尔会有一小块区域
but here and there,
occasionally a little region
停止膨胀，并以正常的速度膨胀
will stop inflating and
just expand at the normal rate.
暴胀可以在某个地方结束
Inflation can end somewhere
从而产生我们所生活的宇宙
and that gives rise
to the universe we live in,
而暴胀则在其他地方继续
while inflation
continues somewhere else.
更大的宇宙中
Narrator:
Parts of the greater universe
继续暴胀的部分
that continued to inflate
会留下不同的物理定律
would be left
with different laws of physics.
这个难以置信的暴胀过程
This incredibly violent
inflation process
实际上与空间本身的结构有关
is actually monkeyed with
the very fabric of space itself,
所以我们学到的很多物理定律
so that a lot of the things
that we were taught
在这里是不一样的
that are laws of physics
are different there.
卡罗尔:从本质上说
Carroll: So in an essence,
暴涨给了我们一种很自然的方式
inflation gives us
a very natural way
让宇宙中不同部分的事物
to make this patchwork quilt of
different parts of the universe
看起来都不一样
where things seem different.
所以我们可以想象一个超大尺度的结构
So what we could imagine
is a super large-scale structure
在宇宙中有不同的区域
where there's different regions
of the universe, domains,
每个区域都有不同的物理定律
and each domain has different
local laws of physics.
宇宙的这些不同部分
Narrator: These different parts
of the universe
被边界隔开，叫做域墙
are separated by frontiers
called domain walls.
我们在地球上也有类似的边界
We have similar boundaries
on earth.
当你有一些东西可以处于许多不同的状态时
Whenever you have something that
can be in many different states,
你最终可能会遇到域墙
you can end up with domain wall.
如果我们的鱼在北极的冰山附近游泳
If our fish swimming around
in the arctic near an iceberg,
在我所在的液态水
there will be a domain boundary
和水以冰形式的固态之间
between the water
being in the liquid state
就会有一个域边界
where I am and the solid state
inside the ice.
所以域墙就是两个域之间的墙
So a domain wall is just a wall
between two domains.
如果是水，墙可以是冰
If it's water,
this could be ice,
相反可以是液体
this could be liquid.
如果你说的是太空
If you're talking about space,
域墙可能是一种你可以居住的空间
this could be a kind of space
maybe you can live in.
域墙就可能是一种你不想呆的地方
This could be a kind of space
where you don't want to be.
对于任何敢于尝试的人来说，跨越域墙
Narrator: Crossing a domain wall
would be very bad news
将是一个非常坏的消息
for anyone who dared to try.
越过这个领域的墙，物理定律
Cross that domain wall
and the laws of physics
就会发生巨大的变化
could change dramatically.
维度的数量可能会改变
The number of dimensions
could change.
如果我们能以某种方式到达宇宙中
If we were somehow able to
travel to places in the universe
物理定律不同的地方
where the laws of physics
are different,
我们会死亡
we would die
因为我们体内发生的所有化学反应
because all of the chemistry
going on in our bodies
都非常非常依赖于物理定律
depends very, very sensitively
on the laws of physics.
所以你可以像灭霸一样消散，然后消失
So you could just dissipate like
thanos snap and you're gone.
域壁可能是我们找到宇宙边缘的
Narrator: Domain walls
might be the closest
最接近的方法
we get to locating
an edge in the universe.
这取决于你如何定义边缘
Depends on how
you define the edge.