Quasirecognizability of simple unitary groups over fields of even order

M. A. Grechkoseeva

Sibirskie èlektronnye matematičeskie izvestiâ, Tome 7 (2010), pp. 435-444.

Résumé

We refer to the set of element orders of a finite group as the spectrum of this group and say that two groups are isospectral if their spectra coincide. We prove that finite simple unitary groups of dimension at least $5$ over fields of characteristic $2$ other than $U_5(2)$ are quasirecognizable by spectrum, that is every finite group isospectral to such unitary group $U$ has a unique nonabelian composition factor and this factor is isomorphic to $U$.

Détail

Keywords: unitary group, element orders, spectrum.

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