The Hochschild cohomology ring of a cyclic block
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- by Stephen F. Siegel and Sarah J. Witherspoon PDF
- Proc. Amer. Math. Soc. 128 (2000), 1263-1268 Request permission
Abstract:
Suppose $B$ is a block of a group algebra $kG$ with cyclic defect group. We calculate the Hochschild cohomology ring of $B$, giving a complete set of generators and relations. We then show that if $B$ is the principal block, the canonical map from $H^*(G,k)$ to the Hochschild cohomology ring of $B$ induces an isomorphism modulo radicals.References
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Additional Information
- Stephen F. Siegel
- Affiliation: Department of Computer Science, University of Massachusetts, Amherst, Massachusetts 01003-4610
- Email: siegel@cs.umass.edu
- Sarah J. Witherspoon
- Affiliation: Department of Mathematics, University of Wisconsin, Madison, Wisconsin 53706
- MR Author ID: 364426
- Email: withersp@math.wisc.edu
- Received by editor(s): March 15, 1998
- Published electronically: February 7, 2000
- Communicated by: Ronald M. Solomon
- © Copyright 2000 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 128 (2000), 1263-1268
- MSC (2000): Primary 20J06, 16E40
- DOI: https://doi.org/10.1090/S0002-9939-00-05466-6
- MathSciNet review: 1691003