makes me recall the compactification on close string indicates T-duality//@田闻川: torus真身是S1＊S1（1是上标）所以猜测三维情况下加上周期边界条件会变成S1＊S1＊S1（可以叫tori）理由是在一维情况下加周期性边界条件会形成S1.//@物语加奶咖: 擦,三维,如果再加上周期性边界条件和什么形状同胚？展开全文
Cohomology de Ram group //@九维空间Sturman: //@文小刚微博: For simple (simple for physicists) definition of Group Cohomology, we wrote an appendix in paper arXiv:1301.0861. (The paper uses Group Cohomology to classify symmetry protect trivial phases, see 🔗 网页链接 )展开全文
Du bist das Phantom in meinem Herzen. Deiner Duft dreht rund um meinen Körper und durchdringt meinen Geist. Es in meinem Gedächtnis und Liebe besteht , was ich nie vergessen kann.展开全文
@李淼在微博 Has Prof.Li ever watch this old film? This true event rasied the question between boss and the students. (for the previous topic and latest news of detecting the cosmic string, so I bring it out~)展开全文
@里奇Rij Any idea ? I can only think of very rough model using Laplace-Yang equation: Δp=2σ/R , Δp=p0+ρgR-p0=ρgR, then suppose ρ=10^3,g=9.8, R=√(2σ/ρg)=3.85978(mm)....展开全文
@里奇Rij Das ist sehr gut !//@zrysbx1: 🔗 网页链接 视频中悉尼大学的助理教授 Mike Wheatland 展示了他的模拟结果. 他的文章发在 2012年12月的AJP上, 这是他关于Slinky 下落的介绍页面🔗 网页链接 有意思的是, W. G. Unruh 在2011年也研究过这个问题. 🔗 网页链接展开全文
@里奇Rij I see those words your professor has said before//@文小刚微博: In 87, the string theory is dominated by CFT. I like to use CFT to study physics, but I do not like to develop the CFT as a math theory. This is the main reason that I switch back to condensed matter physics.展开全文
