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2020/97/1-2 (2) — DOI: 10.5486/PMD.2020.8630 — pp. 27-39

The isomorphism problem of unitary subgroups of modular group algebras

Authors: Zsolt Balogh and Victor Bovdi

Abstract:

Let $V_*({F}G)$ be the normalized unitary subgroup of the modular group algebra ${F}G$ of a finite $p$-group $G$ over a finite field ${F}$ with the classical involution $*$. We investigate the isomorphism problem for the group $V_*({F}G)$, i.e., we pose the question when the group algebra ${F}G$ is uniquely determined by $V_*({F}G)$. We give affirmative answers for classes of finite abelian $p$-groups, $2$-groups of maximal class and non-abelian $2$-groups of order at most $16$.

Keywords: group ring, isomorphism problem, unitary subgroup

Mathematics Subject Classification: 16U60, 16S34, 20C05, 20D15