Mayer-Vietoris squares in algebraic geometry
arXiv:1606.08517 · doi:10.1112/jlms.12575
Abstract
We consider various notions of Mayer--Vietoris squares in algebraic geometry. We use these to generalize a number of gluing and pushout results of Moret-Bailly, Ferrand--Raynaud, Joyet and Bhatt. An important intermediate step is Gabber's rigidity theorem for henselian pairs, which our methods give a new proof of.
26 pages; corrected statement and proof of Proposition 4.2 and overall minor improvements