In this paper: http://arxiv.org/pdf/hep-th/0505016v1.pdf what are the branch(es) of math being used? The unnumbered eq. on the top of page 3 and eq. (7) are good examples. All I've been able to figure out so far is integrating over groups is part of Random Matrix Theory. Group theory is also involved, but that goes without saying.
Thanks for any help!