Transactions of the American Mathematical Society

Author(s): Frauke M. Bleher
Journal: Trans. Amer. Math. Soc. 354 (2002), 3893-3906.
MSC (2000): Primary 20C05; Secondary 16G10
Posted: June 5, 2002
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Abstract: In this paper, the universal deformation rings of certain modular representations of a finite group are determined. The representations under consideration are those which are associated to blocks with Klein four defect groups and whose stable endomorphisms are given by scalars. It turns out that these universal deformation rings are always subquotient rings of the group ring of a Klein four group over the ring of Witt vectors.

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Retrieve articles in Transactions of the American Mathematical Society with MSC (2000): 20C05, 16G10

Frauke M. Bleher
Affiliation: Department of Mathematics, University of Iowa, Iowa City, Iowa 52242-1419
Email: fbleher@math.uiowa.edu

DOI: 10.1090/S0002-9947-02-03072-6
PII: S 0002-9947(02)03072-6
Keywords: Universal deformation rings, Klein four groups, tame blocks
Received by editor(s): October 23, 2001 and, in revised form, April 2, 2002
Posted: June 5, 2002
Additional Notes: The author was supported in part by NSA Young Investigator Grant MDA904-01-1-0050.
Copyright of article: Copyright 2002, American Mathematical Society

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