Universal deformation rings and Klein four defect groups

Bleher, Frauke

doi:10.1090/S0002-9947-02-03072-6

Universal deformation rings and Klein four defect groups
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Trans. Amer. Math. Soc. 354 (2002), 3893-3906 Request permission

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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