An irreducibility criterion for group representations, with arithmetic applications

M. Longo; S. Vigni

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arXiv · 1002.3150

An irreducibility criterion for group representations, with arithmetic applications

M. Longo·S. Vigni

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Abstract

We prove a criterion for the irreducibility of an integral group representation ρover the fraction field of a noetherian domain R in terms of suitably defined reductions of ρat prime ideals of R. As applications, we give irreducibility results for universal deformations of residual representations, with a special attention to universal deformations of residual Galois representations associated with modular forms of weight at least 2.

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M. Longo, S. Vigni. 2010-02-16. An irreducibility criterion for group representations, with arithmetic applications. https://arxiv.org/abs/1002.3150

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