Maximum deconstructibility in module categories
Abstract
We prove that Vop\v{e}nka's Principle implies that for every class of modules over any ring, the class of \textbf{-Gorenstein Projective modules} (\textbf{-}) is a special precovering class. In particular, it is not possible to prove (unless Vop\v{e}nka's Principle is inconsistent) that there is a ring over which the \textbf{Ding Projectives} () or the \textbf{Gorenstein Projectives} () do not form a precovering class (\v{S}aroch previously obtained this result for the class , using different methods). The key innovation is a new "top-down" characterization of \emph{deconstructibility}, which is a well-known sufficient condition for a class to be precovering. We also prove that Vop\v{e}nka's Principle implies, in some sense, the maximum possible amount of deconstructibility in module categories.
Keywords
Cite
@article{arxiv.2012.11084,
title = {Maximum deconstructibility in module categories},
author = {Sean Cox},
journal= {arXiv preprint arXiv:2012.11084},
year = {2021}
}
Comments
accepted version