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Our picture of the earliest moments of the universe has been evolving,
我们对于宇宙最初的认识不断地改变
and I'm happy to say, in some sense has more empirical support than it did before.
我很高兴在某些方面 它得到了比以前更多的实证支持
The discovery of the Higgs field implies that you can get fields that freeze in empty space.
希格斯场的发现暗示着你能够在真空中冷冻
And that's a central part of what we think happened in the very early universe.
它是我们对宇宙初期演变的认知的核心部分
And if we can detect gravitational waves from the Big Bang
如果我们能够探测宇宙大爆炸时产生的引力波
we'd have a window on the universe back to a time when it was a billionth of a billionth of a billionth of a billionth of a second old,
那么我们就能够窥探到一万亿亿亿亿分之一秒时的宇宙是什么样子的
answering questions about the origin of the universe as we know it
回答关于宇宙起源的问题
ideas that I speculated upon in my last book, for example
我的新书中有提到这些猜想
for which we have new evidence that I've described in my new book.
例如书中描述了一些关于这些猜想的新的证据
But because the temperature of the universe and the energies and particles were so extreme at that early time
但是因为在宇宙处于初级阶段的时候其温度 能量和微粒都是处于很极端化的状态的
when the entire visible universe was contained in a region that was smaller than the size of an atom
那时整个宇宙都聚集到一个比原子更小的区域里
there's a wonderful symbiosis between large scales and small scales smaller
在这个尺度上 宏观与微观相差无几
And if we can probe the early universe back to a time that I described we'll actually
如果我们能够探测到我提及的早期宇宙的信号
be probing physics on scales that are much smaller than we can see at the Large Hadron
那么 我们就能够探测到比大型强子对撞机所能获得的还要小的尺度上的物理现象
Collider, 12 orders of magnitude smaller in scale (or higher in energy) than we can probe with our highest-energy accelerator now.
比我们用现有的最高能的加速器所能获得的尺度(或能量)还要小(大)12个数量级
To build an accelerator that would directly probe those energies,
为了建造一个能够直接探测到如此大能量的加速器
we would have to have an accelerator that's not just 26 km around, as the Large Hadron Collider is,
我们必须有一个不仅包含26千米长的大型强子对撞机
but whose circumference is the earth-moon distance
同时 还要包含一个周长要为日月距离的加速器
and that's not going to be built in our lifetime (and probably ever)
我们穷尽一生(可能永远)也无法完成如此规模的加速器
So we may have to rely on the universe to give us new information,
因此 我们只能依靠宇宙自身去给予我们这些信息
and that's why we're looking for such signals.
这就是我们要去探测这些信号的原因
When the universe was a billionth of a billionth of a billionth of a billionth of a second old
当宇宙的年龄是万亿亿亿亿分之一秒时
our current picture suggests: A field very similar to the Higgs field froze in space,
我们现有的图像显示:有一个与希格斯场相似的场冻结于空间中
but it was in what is called a metastable state.
我们称之为亚稳态
Sort of like… if you have a beer party and you put beer in the freezer
就像…你要举办一个啤酒聚会 你将它放入了冷冻格
because you forgot to until the few minutes before the party,
因为你忘了把啤酒冰镇一下 直到聚会马上就要开始了你才想起
and then during the party you forget that it's in the freezer, and you take it out later.
接下来你在参加聚会的时候又忘记放在冷冻格里的啤酒 然后你把它拿出来
And it's there—liquid—and you open it up, and suddenly it turns to ice,
它还在那儿 处于液体状态 然后你打开它 它却在瞬间凝固了
and the bottle cracks: The beer is in a metastable state.
瓶子爆裂:啤酒就处于亚稳态
At that temperature it would rather be frozen except it's under a high pressure.
只有处于高压下 它才能在那样的温度下不冻结
The minute you release the pressure it freezes instantaneously, releasing a lot of energy.
你给它释放压力的瞬间 它就瞬间凝固 并释放很大的能量
As our universe cooled we think the same thing happened;
这跟我们的宇宙冷却时发生的事情是一样的:
basically a field got frozen but in the wrong configuration, and as the universe cooled, suddenly—boom!— like those beer bottles,
只是一个区域冻结了 但是以一种错的方式冻结来了 当宇宙冷却下来的时候 就像啤酒瓶一样砰地一声爆炸了
it changed its state, releasing a huge amount of energy, creating the hot Big Bang.
它改变了自身的状态 释放出大量的能量产生了大爆炸
Now the interesting thing is, while it was in that metastable state and storing energy,
现在 有趣的是 当它处于亚稳态并且储存着能量时
general relativity tells us that if you have a field in empty space that's storing energy
广义相对论告诉我们:如果有个储存着能量的真空场
it produces a gravitational effect that's repulsive, not attractive.
那么它的引力效应为排斥而非吸引
So during that brief time gravity is repulsive, and the expansion of our universe started speeding up faster and faster and faster,
所以有那么短暂的瞬间 引力场为排斥场 然后宇宙大爆炸开始膨胀得越来越快
and the size of our universe (we think) increased by a factor of 10 to the 30th in scale, or at least 10 to the 90th in volume,
宇宙会在一百亿亿分之一秒内将尺度扩大到原来的10的30次方倍
in a time interval of a billionth of a billionth of a billionth of a second.
而体积则至少膨胀为原来的10的90次方倍
That means it went from the size of an atom to the size of a basketball in a short time,
这意味着在很短的时间内 它由一个原子的大小膨胀至一个篮球的大小
and that rapid expansion produced characteristics which pervaded the universe today:
正是由于这剧烈的膨胀导致了遍及整个宇宙的基本的性质:
The fact that our observed universal looks flat, the fluctuations, and the cosmic microwave background
我们观测到的宇宙近乎平坦 涨落与宇宙微波背景辐射
radiation all came from quantum fluctuations that happened during inflation.
都来自于膨胀时的量子涨落
Inflation is the only First Principles idea that in principle explains why our universe looks the way it does.
膨胀是第一原则 它从根本上解释了为什么宇宙会是这样的
And what's wonderful about it is it doesn't require any exotic ideas of quantum gravity or theories we don't have,
值得庆幸 它不需要量子引力以及其它我们还没有建立的理论来提供支持
it's based on ideas that are central to our current understanding
它完全是基于我们现有的
of the standard model of particle physics, just extrapolating them somewhat.
对粒子物理的标准模型的认知 仅仅是标准模型的外推
So it's very well-motivated; even though it is hard to believe that it could have happened, we think it did.
所以 这个很好的解释 即使我们很难相信宇宙大爆炸曾经发生过但是我们认为它发生过
