Gravity vs. Pressure: The battle that formed the universe - Fabio Pacucci

翻译人员: Sophia Ye 校对人员: Jacky He

Welcome one and all!

欢迎大家！

It’s time to grab your seat for the biggest battle

找好座位，准备迎接 即将形成的宇宙中

in the soon-to-be-formed universe.

最激烈的战斗。

That’s right— the Big Bang is about to go down!

没错，宇宙大爆炸即将发生！

In one corner is the force that brings all matter together.

在一角是将所有物质 聚集一起的力量。

It acts on any particle with mass, and its range is infinite—

它作用于任何具有质量的粒子， 不受距离限制——

give it up for gravity!

让我们为重力鼓掌！

In the other corner, our contender can push matter away

在另一角，我们的参与者 能以惊人的力量推开物质。

with spectacular strength.

When the going gets tough, this fighter just gets tougher.

它面对负面情况更为坚韧。

That’s right, it’s pressure!

没错，它就是压力！

Over the next several hundred thousand years,

在接下来的几十万年里，

these two contenders will be wrestling for the fate of the universe.

这两位对手将为宇宙的命运而搏斗。

That’s right folks, the ripple effects of this historic match

没错，各位，这场 历史性决斗的连锁反应

will shape the structure of the universe as we know it today.

将决定我们今天所熟知的宇宙结构。

But what are these powers fighting over?

但这些力量正在比什么？

We’ll find out when the Big Bang hits right... now!

当大爆炸发生时，我们就会知道！

Let’s zoom in for the play-by-play.

让我们接近观察比赛的每一环节。

This epic event has brought three components into our infant universe.

这场史诗般的事件将三个组成部分 带入我们的初代宇宙。

Dark matter, which only interacts with gravity.

暗物质，只与重力相互作用。

Baryonic matter, which makes up all matter you’ve ever seen,

重子物质，构成着 你所见过的一切物质，

is affected by both gravity and pressure.

同时受到重力和压力的影响。

And radiation composed of innumerable particles of light,

以及由无数光的粒子形成的辐射，

also known as photons.

也被称为光子。

In the moments just after the Big Bang,

在大爆炸后的瞬间，

all three components are in equilibrium,

这三个组成部分处于平衡状态，

meaning no one location is denser than another.

意味着没有一个地方是更为密集的。

But as the universe starts expanding, differences in density start to emerge.

但随着宇宙开始膨胀， 密度差异开始体现。

Gravity immediately gets to work pulling matter together.

重力立即开始拉拢物质。

Dark matter begins to collect at the center

黑暗物质开始聚集在

of these increasingly dense regions,

愈加密集区域的中心，

forming the foundations of future galaxies.

构筑未来星系的基础。

Meanwhile, pressure begins gathering its strength.

与此同时，压力也在积聚力量。

In this hot, high-energy environment,

在这个高温、高能量的环境中，

protons and electrons can’t come together to form atoms,

质子和电子无法结合形成原子，

so these loose particles zip around, freely interacting with ambient photons.

因此这些自由粒子在周围的 光子影响下自由运动，

The result is almost a fluid of baryonic matter and radiation.

产生一种带辐射的重子物质流体。

But the closer these baryonic particles get, the hotter the fluid becomes,

但当这些重子粒子彼此靠近时， 流体变得更热，

pushing photons to ping around with incredible force.

使光子以难以置信的力量四处弹射。

This is the power of pressure, specifically radiation pressure,

这就是压力的力量， 具体来说是辐射压力，

battling to push things apart.

将物质分离开来。

With each of gravity’s vicious tugs squeezing photons and matter together,

随着重力每一次强力地 把光子和物质挤压在一起，

pressure exerts a forceful shove back.

压力产生强大的反作用力。

And as the two giants struggle, they heave this fluid back and forth—

当这两个巨人搏斗时， 它们揉捏着这流体——

creating massive waves called baryonic acoustic oscillations.

产生名为重子声学振荡的巨大波纹。

Moving at almost two thirds the speed of light

以近三分之二的光速移动，

these BAOs ripple across space,

这些重子声学振荡在太空中传递，

impacting the universe on the biggest scale imaginable.

对宇宙产生着最为巨大的影响。

These rolling waves determine the distribution of matter throughout space,

这些波纹决定了 物质在空间中的分布；

meaning that today— almost 14 billion years after this fight began—

这意味着今天——这场搏斗 开始将近 140 亿年后——

we're more likely to find galaxies at their peaks

我们更有可能在它们的高峰处找到星系，

and empty space in their troughs.

而它们的波谷中是空旷的。

And that’s not all.

这还不是全部。

We can still see these ripples in the background radiation of the universe,

我们仍然可以在宇宙的 背景辐射中看到这些涟漪，

a permanent reminder of this epic brawl.

它们是这场史诗般的斗争的永久痕迹。

But after being locked in a stalemate for roughly 370,000 years,

但在相持了大约 37 万年后，

the tide of our battle finally begins to turn.

我们战斗的局势终于开始转变。

After all this time, the heat from the Big Bang has dissipated significantly,

经过这么长时间， 大爆炸产生的热量已经显著消散，

cooling the universe down to a temperature

将宇宙冷却到了 电子开始与质子配对的温度。

at which loose electrons start to pair up with protons.

Known as the “era of recombination,”

这被称为“复合时代“，

this stops electrons from recklessly pinging around.

这使得电子不再胡乱碰撞。

This allows light to stream freely for the first time,

这使得光线第一次自由地流动，

illuminating the universe.

照亮了宇宙。

These photons now only exert a tiny force on the neutral atoms they interact with,

这些光子现在只对和它们作用的 中性原子产生微弱的力，

gradually reducing the power of pressure.

逐渐减小了压力的重要性。

And with that, it’s time to crown our champion!

既然这样，是时候 宣布我们的冠军了！

The undefeated force, the most pervasive power in the universe:

不败的力量，宇宙中最普遍的力：

it’s gravity!

重力！

And yet, this rivalry isn’t over.

然而，这场竞争还没有结束。

A similar battle continues between these two sworn enemies today,

类似的战斗仍在今天 在每颗恒星内部持续进行。

within every single star.

As gravity pulls a star’s gas inward,

当重力将恒星的气体向内拉时，

pressure increases and pushes the matter back outward.

压力增加并将物质推向外部。

This push and pull keeps the Sun, and all other stars,

这种推拉使太阳和所有其他恒星

stable for billions of years.

在数十亿年的时间里保持稳定。

In fact, this clash of the titans is the same reason

事实上，这两位巨人的冲突也是

Earth’s atmosphere doesn’t collapse to the ground.

地球大气层不会降至地面的原因。

So while their greatest fight might have ended,

因此，尽管他们 最伟大的战斗已经结束，

these two warriors are still to be locked in combat—

这两位战士仍将继续格斗——

even as a new challenger approaches.

即便一位新的挑战者出现。