了解宇宙是如何运行的（2010）

How the Universe Works S10E05

Part 9 Aug. 5, 2022, 5:05 p.m.

General relativity does
a great job at describing things
尺度上，做得很好
on scales that you and I are
比如行星如何运动
familiar with and things like
how planets move
星系如何演化，所有这些大的东西
and how galaxies evolve,
all the big stuff.
另一方面，量子力学描述的是
Quantum mechanics, on the other
hand, describes the world of
极小的世界，原子的世界
the very small,
the world of the atoms.
问题是这两种理论
The problem is that
these two theories
根本不相符合
don't fit well
together at all.
一种被称为圈量子引力的新理论
A new theory known as
loop quantum gravity,
将量子理论和相对论结合在一起
brings quantum theory
and relativity together,
并做出了一个惊人的预测
and it makes a stunning
prediction.
庞岑:所以一种可能性是，宇宙的终结
PONTZEN: So one possibility
is that the end of the universe
可能与一个新宇宙的开始相吻合
could kind of match onto
the beginning of a new universe
从而创造出一个又一个
and create a cycle
of universes,
宇宙的循环
one after the other.
它被称为大弹跳
Nicknamed the Big Bounce,
预示着宇宙
it predicts a universe that
将停止膨胀并反转
stops expanding and switches
into reverse.
奥卢塞伊:这里的想法是，宇宙可以膨胀一段时间
OLUSEYI: And the idea here is
that the universe can expand for
但会停止膨胀
a time, stop expanding,
然后再次开始收缩
and then begin
to contract again.
有些人认为，也许
And some have suggested
that perhaps
存在一个扩张和压缩的循环
there's a cycle of expanding
and compressing.
它会反弹回来
It bounces back over again.
弹跳模型的吸引力之一是
One of the appeals of
the bouncing model is
它允许我们超越奇点
that it allows us to get
beyond the Singularity.
有点像我们的的回收站
A bit like
recycling on Earth.
所有的组成部分都被粉碎，然后重新利用
All the components get crushed
down and then reused,
这让宇宙没有开始也没有结束
giving the cosmos
no beginning and no end.
如果宇宙是循环的
If the universe is cyclic,
那么年龄还有意义吗？
does the age even have
a meaning?
斯特劳恩:年龄是人类的一种结构
STRAUGHN:
Age is a construct of humanity,
因为我们需要计算时间
because we need to count time.
但如果宇宙是无限的
But if the universe
is infinite,
也许在这大局中它就不重要了
maybe it doesn't matter in
the big scheme of things.
收缩和膨胀的宇宙
A contracting
and expanding universe
扰乱了年龄的概念
messes with the concept
of age.
但宇宙膨胀的观点
But the very idea of
提供了另一个宇宙曲线球概念
an expanding universe provides
another cosmic curveball.
它可能不是唯一的——
It might not be alone --
it might
它可能只是众多永恒宇宙中的一个
be just one ageless universe
among many.
这是一个嵌入在大爆♥炸♥数学中的想法
It's an idea embedded in
the math of the Big Bang.
天体物理学中最流行的理论是
The most popular theory
we have in astrophysics,
宇宙大爆♥炸♥是由暴涨引起的
what put the bang into
our Big Bang, is inflation.
该观点认为有一种巨大的暗能量
This idea that there was
a kind of dark energy
使我们的宇宙不断地翻倍
on steroids that made our
universe double over and over
不是每七十亿年一次
not every seven billion years,
而是每一秒一次
but every split second,
从几乎没有任何物质中，产生一次大爆♥炸♥
creating out of
almost nothing, a big bang.
当宇宙只有
When the universe was just
a hundredth of a billionth
一亿亿亿亿亿分之一秒时
of a trillionth of
a trillionth of a second old,
它经历了一个快速膨胀的时期，称为暴胀
it underwent a period of rapid
expansion called inflation.
它的体积翻了至少90倍
It doubled in size at least
90 times, going from
从亚原子粒子的大小变成了
the size of a subatomic
particle to that of
高尔夫球的大小
a golf ball.
特马克:暴胀理论的问题是
TEGMARK: The problem with this
inflation is that
它并没有真正停止
it doesn't really stop.
它只是让这个空间变得更大
It just makes this ever bigger
space and says that,
是的，好吧，有一个区域的空间
yeah, well, okay, there was
one region of space where
停止了这种疯狂的倍增现象并且形成了星系
this crazy doubling stopped
and galaxies formed,
那就是我们
and that's us.
但在这个广阔的领域，暴胀
But there's this vast realm
out there where inflation is
仍在发生
still happening.
在暴胀停止的地方
In the spots
where inflation stops,
平行宇宙就形成了
parallel universes form.
这种永恒的暴胀意味着
This eternal inflation
means that
新的宇宙不断地出现
new universes are popping into
existence all the time,
但它们之间是完全分离的
but they're completely separated
one from the other.
特马克:我的许多同事讨厌平行宇宙
TEGMARK: Many of my colleagues
hate parallel universes.
他们只是不喜欢这样的想法，我们的宇宙
They just don't like the idea
that our universe is
如此之大，其中大部分对我们来说都是禁区
so big and most of it is
off limits for us.
如果你愿意谦逊一点，接受这个
If you are willing to be a bit
more humble and accept
宇宙可能比我们看到的
that the reality might be
much, much bigger
要大得多的事实
than we will ever see,
那么平行宇宙就会觉得很自然了
then parallel universes
feel pretty natural.
奥卢塞伊:宇宙中所有的东西是如何联♥系♥在一起的
OLUSEYI: It's really interesting
how everything
这真的很有趣
in the universe is
tied together.
我们可以从一个简单的问题开始
We can start with a simple
question like how old is
比如宇宙的年龄，而我们现在
the universe, and here we are,
questioning virtually
几乎质疑宇宙的一切
everything about the universe.
宇宙学对宇宙的年龄
Cosmology's
长达一个世纪的探索
century-long search for
the age of the universe
迫使我们质疑我们的宇宙学模型
forces us to question
our cosmological model,
引力的本质，甚至时间本身
the nature of gravity,
and even time itself.
宇宙的年龄确实带来了一些
The age of the universe
does bring up sort of
深奥的哲学问题
profound philosophical
questions about how
关于宇宙是如何开始的
a universe can even start,
你是如何从无到有创造出东西的？
how can you create something
from nothing?
塞勒:无论宇宙是什么
THALLER:
The vast majority of whatever
它的绝大部分都永远不为我们所知
the universe is,
is eternally hidden to us.
所以我们回答了这个有多大，有多老的问题
So we answered the questions
how big, how old,
这些答案告诉我们，我们甚至不知道
and those very answers
show us that we don't
我们是否一开始就问了正确的问题
<又是“说了个寂寞”的一集，不过至少让我们知道了>
<目前天文家发展到了什么程度，以及现在瓶颈是什么>
even know if we've asked the
right questions to begin with.