English

Compact generators of the contraderived category of contramodules

Category Theory 2024-12-31 v1 Rings and Algebras

Abstract

We consider the contraderived category of left contramodules over a right linear topological ring R\mathfrak R with a countable base of neighborhoods of zero. Equivalently, this is the homotopy category of unbounded complexes of projective left R\mathfrak R-contramodules. Assuming that the abelian category of discrete right R\mathfrak R-modules is locally coherent, we show that the contraderived category of left R\mathfrak R-contramodules is compactly generated, and describe its full subcategory of compact objects as the opposite category to the bounded derived category of finitely presentable discrete right R\mathfrak R-modules. Under the same assumptions, we also prove the flat and projective periodicity theorem for R\mathfrak R-contramodules.

Keywords

Cite

@article{arxiv.2412.20494,
  title  = {Compact generators of the contraderived category of contramodules},
  author = {Leonid Positselski and Jan Stovicek},
  journal= {arXiv preprint arXiv:2412.20494},
  year   = {2024}
}

Comments

LaTeX 2e with mathrsfs and xy-pic; 54 pages, 6 commutative diagrams