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Algebraic deformations arising from orbifolds with discrete torsion

Andrei Caldararu·Anthony Giaquinto·Sarah Witherspoon
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Abstract

We develop methods for computing Hochschild cohomology groups and deformations of crossed product rings. We use these methods to find deformations of a ring associated to a particular orbifold with discrete torsion, and give a presentation of the center of the resulting deformed ring. This connects with earlier calculations by Vafa and Witten of chiral numbers and deformations of a similar orbifold.

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Andrei Caldararu, Anthony Giaquinto, Sarah Witherspoon. 2003-08-08. Algebraic deformations arising from orbifolds with discrete torsion. https://arxiv.org/abs/math/0210027

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