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Iwasawa invariants of Galois deformations

Tom Weston
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Abstract

We study the behavior of Iwasawa invariants among ordinary deformations of a fixed residual Galois representation taking values in a reductive algebraic group G. In particular, under the assumption that these Selmer groups are cotorsion modules over the Iwasawa algebra, we show that the vanishing of the mu invariant is independent of the deformation, while the lambda invariant depends only on the ramification. This generalizes work of Greenberg-Vatsal and Emerton-Pollack and the author in the case G = GL(2).

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Tom Weston. 2004-05-26. Iwasawa invariants of Galois deformations. https://arxiv.org/abs/math/0405505

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