This site collects some of my understandings and thinkings on both mathematics and physics. I used to take notes on nothing because I think it waste my time on copying things from textbooks. However, with the largely increasement of amount of books I read these years, I forget things and have no much time review. It seems good to write a few essays recapitulating main ideas of numerous beauties that puzzle and eventually thrill me. Then arises the site.
I welcome any comments and discussions here about maths and physics. Suggestions on what to write and how to build the site are also encouraged.