English

Exterior powers and Tor-persistence

Commutative Algebra 2024-07-29 v4 Rings and Algebras

Abstract

A commutative Noetherian ring RR is said to be Tor-persistent if, for any finitely generated RR-module MM, the vanishing of ToriR(M,M)\operatorname{Tor}_i^R(M,M) for i0i\gg 0 implies MM has finite projective dimension. An open question of Avramov, et. al. asks whether any such RR is Tor-persistent. In this work, we exploit properties of exterior powers of modules and complexes to provide several partial answers to this question; in particular, we show that every local ring (R,m)(R,\mathfrak{m}) with m3=0\mathfrak{m}^3=0 is Tor-persistent. As a consequence of our methods, we provide a new proof of the Tachikawa Conjecture for positively graded rings over a field of characteristic different from 2.

Keywords

Cite

@article{arxiv.2007.09174,
  title  = {Exterior powers and Tor-persistence},
  author = {Justin Lyle and Jonathan Montaño and Keri Sather-Wagstaff},
  journal= {arXiv preprint arXiv:2007.09174},
  year   = {2024}
}
R2 v1 2026-06-23T17:12:20.712Z