Fractional Brauer configuration algebras II: covering theory
Abstract
In this paper, we develop a covering theory for the fractional Brauer configurations and connect it with the coverings of the associated quivers with relations in the sense of Mart\'inez-Villa and de la Pe\~na. Among the results, we show the following: (1) The universal cover of any fractional Brauer configuration is simply connected and we construct explicitly the universal cover of fractional Brauer configurations of type MS; (2) The fundamental group of a fractional Brauer configuration of type S is isomorphic to the fundamental group of the associated quiver with relations ; (3) A (regular) covering of fractional Brauer configurations induces a (Galois) covering of the associated fractional Brauer configuration categories; (4) Set up an analogy of Van Kampen theorem for fractional Brauer configurations and apply it to calculate the fundamental group of any connected Brauer configuration.
Keywords
Cite
@article{arxiv.2412.13445,
title = {Fractional Brauer configuration algebras II: covering theory},
author = {Nengqun Li and Yuming Liu},
journal= {arXiv preprint arXiv:2412.13445},
year = {2026}
}
Comments
50 pages