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Products in Hochschild cohomology and Grothendieck rings of group crossed products

Sarah J. Witherspoon
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Abstract

We give a general construction of rings graded by the conjugacy classes of a finite group. Some examples of our construction are the Hochschild cohomology ring of a finite group algebra, the Grothendieck ring of the Drinfel'd double of a group, and the orbifold cohomology ring for a global quotient. We generalize the first two examples by deriving product formulas for the Hochschild cohomology ring of a group crossed product and for the Grothendieck ring of an abelian extension of Hopf algebras. Our results account for similarities in the product structures among these examples.

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BibTeXRIS

Sarah J. Witherspoon. 2002-11-30. Products in Hochschild cohomology and Grothendieck rings of group crossed products. https://arxiv.org/abs/math/0212003

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