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A Calabi-Yau threefold with Brauer group (Z/8Z)^2

Mark Gross·Simone Pavanelli
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Abstract

We calculate the Brauer group of a certain Calabi-Yau threefold discovered by Mark Gross and Sorin Popescu, which is a small resolution of a complete intersection of type (2,2,2,2) with 64 ordinary double points. We find the Brauer group is (Z/8Z)^2, which is the largest known example of a Brauer group of a Calabi-Yau threefold.

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Mark Gross, Simone Pavanelli. 2005-12-09. A Calabi-Yau threefold with Brauer group (Z/8Z)^2. https://arxiv.org/abs/math/0512182

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