TED演讲：宏观历史(4)

 　　And this is how it works. Gravity is more powerful where there's more stuff. 这就是它怎么运作的。重力场的作用力更大，拥有比较多的物质。

　　So where you get slightly denser¹ areas, gravity starts compacting clouds of hydrogen and helium atoms. 所以这里我们有个密度稍微大的区域，重力场开始凝结成氢氦原子的原子云。

　　So we can imagine the early universe breaking up into a billion clouds. 我们能想象早期宇宙散布在十亿的原子云中。

　　And each cloud is compacted, gravity gets more powerful as density² increases, 每片云都是紧凑的，重力场就随着密度的增加而效果更加明显，

　　the temperature begins to rise at the center of each cloud, and then, at the center, 在每片云的中心温度开始升高，而且在每片云的中心，

　　the temperature crosses the threshold temperature of 10 million degrees, protons start to fuse, 温度超过了阈温度之上一千万度，质子开始融合，

　　there's a huge release of energy, and -- bam! We have our first stars. 这释放出大量的能量，接着，轰！我们就有了第一颗恒星。

　　From about 200 million years after the Big Bang, stars begin to appear all through the universe, billions of them. 大约距离大爆炸之后的2亿年，恒星开始在整个宇宙出现，成千上万的恒星。

　　And the universe is now significantly more interesting and more complex. 宇宙现在开始相当的有趣，也更加复杂。

　　Stars will create the Goldilocks conditions for crossing two new thresholds. 恒星开始创作黄金条件来超越两个新的起始点。

　　When very large stars die, they create temperatures so high that protons begin to fuse in all sorts of exotic combinations, 当巨大的星系泯灭的时候，它们有着很高的温度，以至于质子开始融合进入各种奇异混合物中，

　　to form all the elements of the periodic table. If, like me, you're wearing a gold ring, it was forged in a supernova explosion. 来形成在元素周期表上的所有元素。就好像，你正带着一个黄金的戒指，它是天体爆炸而铸就的。

　　So now the universe is chemically more complex. 所以现在的宇宙在化学程度上是更加复杂的。

　　And in a chemically more complex universe, it's possible to make more things. 对于一个化学程度上更加复杂的宇宙而言，就有可能做更多的事情。

　　And what starts happening is that, around young suns, young stars, all these elements combine, 然后要开始产生的是新生的太阳，新生的恒星，所有的元素结合，

　　they swirl³ around, the energy of the star stirs them around, they form particles, they form snowflakes, 它们在一起旋转，星球的能量搅拌它们，它们形成微粒，形成雪花，

　　they form little dust motes⁴, they form rocks, they form asteroids⁵, and eventually, they form planets and moons. 形成微小的灰尘微粒，它们形成岩石，形成小行星，最后它们形成行星和月亮。

　　And that is how our solar system was formed, four and a half billion years ago. 这就是我们太阳系在45亿年前形成的过程。

　　Rocky planets like our Earth are significantly more complex than stars because they contain a much greater diversity of materials. 岩石型的行星，比如地球，比起其他恒星就明显更加复杂了，因为它们包含了更加多样性的物质。

　　So we've crossed a fourth threshold of complexity⁶. 因此我们已经穿过了第四个复杂性的起始点。

1 denser   

adj. 不易看透的, 密集的, 浓厚的, 愚钝的

参考例句：

• The denser population necessitates closer consolidation both for internal and external action. 住得日益稠密的居民，对内和对外都不得不更紧密地团结起来。 来自英汉非文学 - 家庭、私有制和国家的起源
• As Tito entered the neighbourhood of San Martino, he found the throng rather denser. 蒂托走近圣马丁教堂附近一带时，发现人群相当密集。

2 density   

n.密集，密度，浓度

参考例句：

• The population density of that country is 685 per square mile.那个国家的人口密度为每平方英里685人。
• The region has a very high population density.该地区的人口密度很高。

3 swirl   

v.(使)打漩，(使)涡卷；n.漩涡，螺旋形

参考例句：

• The car raced roughly along in a swirl of pink dust.汽车在一股粉红色尘土的漩涡中颠簸着快速前进。
• You could lie up there,watching the flakes swirl past.你可以躺在那儿，看着雪花飘飘。

4 motes   

n.尘埃( mote的名词复数 )；斑点

参考例句：

• In those warm beams the motes kept dancing up and down. 只见温暖的光芒里面，微细的灰尘在上下飞扬。 来自辞典例句
• So I decided to take lots of grammar motes in every class. 因此我决定每堂课多做些语法笔记。 来自互联网

5 asteroids   

n.小行星( asteroid的名词复数 )；海盘车，海星

参考例句：

• Asteroids,also known as "minor planets",are numerous in the outer space. 小行星，亦称为“小型行星”，在外太空中不计其数。
• Most stars probably have their quota of planets, meteorids, comets, and asteroids. 多数恒星也许还拥有若干行星、流星、彗星和小行星。

6 complexity   

n.复杂(性)，复杂的事物

参考例句：

• Only now did he understand the full complexity of the problem.直到现在他才明白这一问题的全部复杂性。
• The complexity of the road map puzzled me.错综复杂的公路图把我搞糊涂了。