On quiver Grassmannians and orbit closures for gen-finite modules

TL;DR

This paper develops a method to desingularize orbit closures and quiver Grassmannians for gen-finite modules over finite-dimensional algebras using canonical tilting modules and recollements, extending previous results.

Contribution

It introduces a new approach to desingularize orbit closures and quiver Grassmannians for gen-finite modules via canonical tilts and recollements, generalizing prior work.

Findings

Constructed desingularisations of orbit closures.

Extended results to cogen-finite modules.

Connected tilting theory with geometric desingularisation.

Abstract

We show that endomorphism rings of cogenerators in the module category of a finite-dimensional algebra A admit a canonical tilting module, whose tilted algebra B is related to A by a recollement. Let M be a gen-finite A-module, meaning there are only finitely many indecomposable modules generated by M. Using the canonical tilts of endomorphism algebras of suitable cogenerators associated to M, and the resulting recollements, we construct desingularisations of the orbit closure and quiver Grassmannians of M, thus generalising all results from previous work of Crawley-Boevey and the second author in 2017. We provide dual versions of the key results, in order to also treat cogen-finite modules.