A formula for the mod $p$ cohomology of $BPU(p)$
Algebraic Topology
2025-11-18 v3
Abstract
We study the mod cohomology ring of the classifying space of the projective unitary group , when is an odd prime. We prove a mod formula analogous to a formula of Vistoli for the integral cohomology ring of . As an application, we give a simple topological proof of Vistoli's formula.
Cite
@article{arxiv.2503.23399,
title = {A formula for the mod $p$ cohomology of $BPU(p)$},
author = {Feifei Fan},
journal= {arXiv preprint arXiv:2503.23399},
year = {2025}
}
Comments
10 pages. Final version, to appear in Proc. Amer. Math. Soc