The bigger Brauer group and twisted sheaves

Jochen Heinloth; Stefan Schroeer

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arXiv · 0803.3563

The bigger Brauer group and twisted sheaves

Jochen Heinloth·Stefan Schroeer

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Abstract

Given an algebraic stack with quasiaffine diagonal, we show that each G_m-gerbe comes from a central separable algebra. In other words, Taylor's bigger Brauer group equals the etale cohomology in degree two with coefficients in G_m. This gives new results also for schemes. We use the method of twisted sheaves explored by de Jong and Lieblich.

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Jochen Heinloth, Stefan Schroeer. 2008-03-25. The bigger Brauer group and twisted sheaves. https://arxiv.org/abs/0803.3563

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