What's the current state of Yang–Mills mass gap question, is there any place that does this problem? Especially I want to know if there is any progress (out of that mentioned in the introduction article by Witten and Jaffe). Is it too hard for a mathematician? Thanks!



What's the current state of Yang–Mills mass gap question?
There's some guidelines about open problems in the FAQ that you might want to read, but there was a good article by Faddeev last November that you should know about:


[Mass in Quantum Yang-Mills Theory, by Faddeev](http://arxiv.org/abs/0911.1013)


