主题：【原创】这得从人与宇宙的关系开始讲起（一） -- 陈经

I guess in string theory, they are talking about a fiber bundle, which has a Lorenz manifold (or just the Minkowski space) as its base, and Calabi-Yau manifold as its fiber. They may also assume that the bundle is trivial. Not very sure.

可能哲学在现实生活中没有“实用价值”，但是哲学的“无用之用”是科学，技术永远无法代替和超越的！