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arXiv · 2404.14615

On local Galois deformation rings: generalised tori

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 tori, such as $L$-groups of (possibly non-split) tori. We show that the corresponding deformation rings are formally smooth over a group algebra of a finite abelian $p$-group. We compute their dimension and the set of irreducible components.

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Vytautas Paškūnas, Julian Quast. 2024-04-22. On local Galois deformation rings: generalised tori. https://doi.org/10.1017/fms.2024.137

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