Publication details

Character tables and defect groups

Authored by

Benjamin Sambale

Abstract

Let B be a block of a finite group G with defect group D. We prove that the exponent of the center of D is determined by the character table of G. In particular, we show that D is cyclic if and only if B contains a “large” family of irreducible p-conjugate characters. More generally, for abelian D we obtain an explicit formula for the exponent of D in terms of character values. In small cases even the isomorphism type of D is determined in this situation. Moreover, it can read off from the character table whether |D/D|=4 where D denotes the commutator subgroup of D. We also propose a new characterization of nilpotent blocks in terms of the character table.

Details

Organisation(s)
Institute of Algebra, Number Theory and Discrete Mathematics
Type
Article
Journal
Journal of algebra
Volume
562
Pages
323-340
No. of pages
18
ISSN
0021-8693
Publication date
15.11.2020
Publication status
Published
Peer reviewed
Yes
ASJC Scopus subject areas
Algebra and Number Theory
Electronic version(s)
https://doi.org/10.48550/arXiv.2007.04919 (Access: Open )
https://doi.org/10.1016/j.jalgebra.2020.05.040 (Access: Closed )
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