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arXiv · 1304.2691

The Bogomolov multiplier of rigid finite groups

Ming-chang Kang·Boris Kunyavskii
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Abstract

The Bogomolov multiplier of a finite group $G$ is defined as the subgroup of the Schur multiplier consisting of the cohomology classes vanishing after restriction to all abelian subgroups of $G$. This invariant of $G$ plays an important role in birational geometry of quotient spaces $V/G$. We show that in many cases the vanishing of the Bogomolov multiplier is guaranteed by the rigidity of $G$ in the sense that it has no outer class-preserving automorphisms.

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Ming-chang Kang, Boris Kunyavskii. 2013-04-09. The Bogomolov multiplier of rigid finite groups. https://arxiv.org/abs/1304.2691

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