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arXiv · 1204.0071

Brauer's generalized decomposition numbers and universal deformation rings

Frauke M. Bleher
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Abstract

The versal deformation ring R(G,V) of a mod p representation V of a profinite group G encodes all isomorphism classes of lifts of V to representations of G over complete local commutative Noetherian rings. We introduce a new technique for determining R(G,V) when G is finite which involves Brauer's generalized decomposition numbers.

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Frauke M. Bleher. 2012-03-31. Brauer's generalized decomposition numbers and universal deformation rings. https://doi.org/10.1090/s0002-9947-2014-06120-5

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