Relative Brauer Groups and étale cohomology

Vivek Sadhu

In this article, we construct a natural group homomorphism $$\psi :\text{Br}(f)\to H_{et}^1(S,f_{\ast }{\mathcal{O}}_X^{\times }/{\mathcal{O}}_S^{\times })$$ for a faithful affine map $…