Saved in:
Bibliographic Details
Main Author: Geiß, Christof
Format: Preprint
Published: 2023
Subjects:
Online Access:https://arxiv.org/abs/2307.10306
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866917020003467264
author Geiß, Christof
author_facet Geiß, Christof
contents Let $K$ be an algebraically closed field with $\operatorname{char}(K)\neq 2$, and $A$ a skewed-gentle $K$-algebra. In this case, Crawley-Boevey's description of the indecomposable $A$-modules becomes particularly easy. This allows us to provide an explicit basis for the homomorphisms between any two indecomposable representations in terms of the corresponding admissible words in the sense of Qiu and Zhou. Previously (Geiss, 1999), such a basis was only available when no asymmetric band modules were involved. We also extend a relaxed version of fringing and kisses from Brüstle et al. (2020) to the setting of skewed-gentle algebras. With this at hand, we obtain convenient formulae for the E-invariant and g-vector for indecomposable $A$-modules, similar to the known expressions for gentle algebras. Note however, that we allow in our context also band-modules. As an application, we describe the indecomposable, generically $τ$-regular irreducible components of the representation varieties of $A$ as well as the generic values of the E-invariant between them in terms of tagged admissible words.
format Preprint
id arxiv_https___arxiv_org_abs_2307_10306
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle On homomorphisms and generically $τ$-regular components for skewed-gentle algebras
Geiß, Christof
Representation Theory
16G10, 16G70
Let $K$ be an algebraically closed field with $\operatorname{char}(K)\neq 2$, and $A$ a skewed-gentle $K$-algebra. In this case, Crawley-Boevey's description of the indecomposable $A$-modules becomes particularly easy. This allows us to provide an explicit basis for the homomorphisms between any two indecomposable representations in terms of the corresponding admissible words in the sense of Qiu and Zhou. Previously (Geiss, 1999), such a basis was only available when no asymmetric band modules were involved. We also extend a relaxed version of fringing and kisses from Brüstle et al. (2020) to the setting of skewed-gentle algebras. With this at hand, we obtain convenient formulae for the E-invariant and g-vector for indecomposable $A$-modules, similar to the known expressions for gentle algebras. Note however, that we allow in our context also band-modules. As an application, we describe the indecomposable, generically $τ$-regular irreducible components of the representation varieties of $A$ as well as the generic values of the E-invariant between them in terms of tagged admissible words.
title On homomorphisms and generically $τ$-regular components for skewed-gentle algebras
topic Representation Theory
16G10, 16G70
url https://arxiv.org/abs/2307.10306