Abstract
Let G be a finite group and F a field. We give an elementary proof that the group of normalized cohomological invariants of G over F with values in the Brauer group is isomorphic to \({{\,\mathrm{\mathrm {H}}\,}}^{2}(G,F^{\times })\).
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Acknowledgements
I would like to thank David McNeilly for discussions about and around the Schur multiplier of a finite group, and Volodya Chernousov for useful comments.
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The author has been supported by an NSERC Grant.
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Gille, S. On Brauer invariants of finite groups. Math. Z. 300, 217–234 (2022). https://doi.org/10.1007/s00209-021-02773-z
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DOI: https://doi.org/10.1007/s00209-021-02773-z