# Twisted sheaves and the period-index problem

@article{Lieblich2008TwistedSA, title={Twisted sheaves and the period-index problem}, author={Max Lieblich}, journal={Compositio Mathematica}, year={2008}, volume={144}, pages={1 - 31} }

Abstract We use twisted sheaves and their moduli spaces to study the Brauer group of a scheme. In particular, we (1) show how twisted methods can be efficiently used to re-prove the basic facts about the Brauer group and cohomological Brauer group (including Gabber’s theorem that they coincide for a separated union of two affine schemes), (2) give a new proof of de Jong’s period-index theorem for surfaces over algebraically closed fields, and (3) prove an analogous result for surfaces over…

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