Ştefan spectral sequence for faithfully flat Hopf Galois extensions is multiplicative

Liyu Liu, Hongguang Nie, Guodong Zhou +1

Let $H$ be a Hopf algebra with a bijective antipode over a field $\mathbf{k}$ and $B/A$ be a flat right $H$-Galois extension. Ştefan constructed a spectral sequence converging to th…