# Unramified Brauer groups of finite and infinite groups

@article{Moravec2012UnramifiedBG, title={Unramified Brauer groups of finite and infinite groups}, author={Primoz Moravec}, journal={American Journal of Mathematics}, year={2012}, volume={134}, pages={1679 - 1704} }

The Bogomolov multiplier is a group theoretical invariant isomorphic to the unramified Brauer group of a given quotient space. We derive a homological version of the Bogomolov multiplier, prove a Hopf-type formula, find a five term exact sequence corresponding to this invariant, and describe the role of the Bogomolov multiplier in the theory of central extensions. A new description of the Bogomolov multiplier of a nilpotent group of class two is obtained. We define the Bogomolov multiplier…

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## 47 Citations

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