——致这个美丽而变动不居的秋天

Warning: 这是一篇科普. 面向人类的内容在正文, 面向非人类的内容放在引用框中.

## 一

Not finished yet!

Closed quantum systems, without noise.

Quantum opsrations formalism, to describe open quantum systems. It can be applied to any kind of open systems and can be used to describe discrete state changes.