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arXiv · 2404.14622

On local Galois deformation rings: generalised reductive groups

Vytautas Paškūnas·Julian Quast
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Abstract

We study deformation theory of mod $p$ Galois representations of $p$-adic fields with values in generalised reductive group schemes, such as $L$-groups and $C$-groups. We show that the corresponding deformation rings are complete intersections of expected dimension. We determine their irreducible components in many cases and show that they and their special fibres are normal and complete intersection.

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Vytautas Paškūnas, Julian Quast. 2024-04-22. On local Galois deformation rings: generalised reductive groups. https://doi.org/10.1017/fmp.2026.10030

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