On local Galois deformation rings: generalised tori

Paškūnas, Vytautas  ; Quast, Julian 

Forum of Mathematics, Sigma, Tome 13 (2025) no. 1, p. e45

Résumé

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.

Détail

DOI : 10.1017/fms.2024.137

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