高度精密的宇宙，都是巧合吗？

昨天我教弟子jonahill说道：“这么有规律的世界，不是simulation的话实在是很神奇啊。”我刚好最近看了一本书，Three Big Bangs, by Holmes Rolston。里面讲了六点让人惊讶的精密，来这里总结一下（也是给自己备份一下）。

1. 宇宙扩张的速度取决于cosmological constant, 是个小于10的-120次方的数。

霍金曾说，why is the universe so close to the line between collapsing again and expanding indefinitely? In order to be as close as we are now, the rate of expansion one second after the big bang had to be chosen fantastically

accurately. If it's less by one part in 10 to the 10th (10的10次方分之一）， the universe would have collapsed after a few millions years. If it's greater than 10的10次方分之一, the universe could have been essentially empty after a few million years.

2. 所有星系星球的产生，还有一个中间数定理。比如星球大小刚好是宇宙和原子大小的geometric mean。人的质量刚好是质子和地球质量的geometric mean。任何midrange scale 是能够最大限度产生complexity的。这点最重要。

3.The four fundamental forces，其大小差别有40 orders or magnitude。但是所有的推力和拉力刚好hold things together。差一点的话，星星就会烧的太快或者太慢，从而阻止生命的成长。比如如果质子间的引力高几个百分比的话，所有的氢就都会变成氦。任何星体都不会产生了。

4.碳和氧原子是生命中最重要的。A change of >

0.5% in the strong interaction of>

4% in the electromagnetic force would destroy nearly all C and O in every star.

5.有个常数alpha，叫fine structure constant. 1/137.035999070，如果这个常数变了，能够存在的元素数就变了。 

6.对称性破坏是一切复杂性的源泉。没怎么看懂。