Cohomological support varieties under local homomorphisms
Abstract
Given a bounded complex of finitely generated modules over a commutative noetherian local ring , one assigns to it a variety, , called the cohomological support variety of over . The variety holds important homological information about the complex and the ring. In this paper, we study the behavior of cohomological support varieties under restriction of scalars along local maps. In the case where the rings involved are complete intersections and the map is a surjective complete intersection, this recovers a theorem of Bergh and Jorgensen. Additionally, we show that if is a local map of finite flat dimension, then the dimension of is less than or equal to that of . This allows us to recover Avramov's result that the complete intersection property is preserved under localization.
Cite
@article{arxiv.2506.10757,
title = {Cohomological support varieties under local homomorphisms},
author = {Ryan Watson},
journal= {arXiv preprint arXiv:2506.10757},
year = {2025}
}
Comments
18 pages