The Stacks project

Slogan by Ariyan Javanpeykar

Flat base change of cohomology

	The proof is only sketched so far. We opt for a different proof
	than in the case of schemes. Namely, we want to use Lazard's
	theorem combined with the fact that cohomology commutes with
	filtered colimits on quasi-compact and quasi-separated algebraic
	spaces (which is a good thing to have available anyway).

	Details to follow.

Tags: Added new tags

Criteria for quotient stacks to be algebraic

	The most interesting result is that [S/G] is an algebraic stack
	if and only if G ---> S is flat and locally of finite
	presentation. The proof uses a fun lemma on the descent of
	flatness (see the change in descent.tex).