Homological degrees of representations of categories with shift functors
Abstract
Let be a commutative Noetherian ring and be a locally finite -linear category equipped with a self-embedding functor of degree 1. We show under a moderate condition that finitely generated torsion representations of are super finitely presented (that is, they have projective resolutions each term of which is finitely generated). In the situation that these self-embedding functors are genetic functors, we give upper bounds for homological degrees of finitely generated torsion modules. These results apply to quite a few categories recently appearing in representation stability theory. In particular, when is a field of characteristic 0, we obtain another upper bound for homological degrees of finitely generated -modules.
Keywords
Cite
@article{arxiv.1507.08023,
title = {Homological degrees of representations of categories with shift functors},
author = {Liping Li},
journal= {arXiv preprint arXiv:1507.08023},
year = {2015}
}
Comments
Major changes include: A stronger upper bound for homological degrees of torsion modules; a new proof of the Koszulity of categories with shift functors; a new upper bound for homological degrees of FI-modules, etc