Finding Supercharacter Theories on Character Tables
Representation Theory
2023-03-20 v2 Group Theory
Abstract
We describe an easy way how to find supercharacter theories for a finite group, if its character table is known. Namely, we show how an arbitrary partition of the conjugacy classes or of the irreducible characters can be refined to the coarsest partition that belongs to a supercharacter theory. Our constructions emphasize the duality between superclasses and supercharacters. An algorithm is presented to find all supercharacter theories on a given character table. The algorithm is used to compute the number of supercharacter theories for some nonabelian simple groups with up to 26 conjugacy classes.
Cite
@article{arxiv.2009.13590,
title = {Finding Supercharacter Theories on Character Tables},
author = {Frieder Ladisch},
journal= {arXiv preprint arXiv:2009.13590},
year = {2023}
}
Comments
18 pages, ancillary file with GAP code; v2: fixed grammar, typos; has been published in Comm. Algebra