This is hard to me since I am a mathematician/statistician

來源: 於 2018-11-07 06:45:22 [舊帖] [給我悄悄話] 本文已被閱讀：次

I did read the book "String Theory" by Witten in early 1990s, but I did not understand it. In the book, it is full of formal calculations which are not rigorous math (could be formal phyical descriptions).