A construction of simple-minded systems over domestic Brauer graph algebras I: the 2-domestic case
Zhen Zhang
TL;DR
This work provides a complete framework for constructing and classifying simple-minded systems in the stable module category of 2-domestic Brauer graph algebras. By explicitly building orthogonal systems on Euclidean components and on quasi-tubes, and then combining them, the authors produce sms that coincide with all sms in this setting, along with a new proof of the AR-conjecture for 2-domestic algebras. A key technical tool is the stable bi-perpendicular category, whose explicit rectangle/triangle descriptions for objects on Euclidean components and quasi-tubes enable precise control of Hom-spaces and extension-closure. The results show that any maximal orthogonal system containing Euclidean data extends to an sms with a functorially finite extension-closure, and that weakly sms with finite cardinality are sms, contributing to a robust understanding of stable representation theory for this tame, representation-infinite class.
Abstract
Let $A$ be a 2-domestic Brauer graph algebra. We present a construction for a family of objects on $A$-$\stmod$ to be a simple-minded system and our construction provides all simple-minded systems on $A$-$\stmod$. As a byproduct, we provide a new proof of AR-conjecture for 2-domestic Brauer graph algebras and we prove that a weakly simple-minded system with a finite cardinality is a simple-minded system on $A$-$\stmod$. We also prove that an orthogonal system $\mathcal{S}$ which contains at least one object for an Euclidean component extends to a simple-minded system on $A$-$\stmod$ and its extension closure $\mathcal{F}(\mathcal{S})$ is functorially finite.
