On the Hilbert eigenvariety at exotic and CM classical weight 1 points

Abstract Let F be a totally real number field and let f be a classical cuspidal p-regular Hilbert modular eigenform over F of parallel weight 1. Let x be the point on the p-adic Hilbert eigenvariety $${\mathcal...

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Bibliographic Details
Main Authors: Betina, Adel, Deo, Shaunak V., Fité, Francesc
Other Authors: Massachusetts Institute of Technology. Department of Mathematics
Format: Article
Language:English
Published: Springer Berlin Heidelberg 2021
Online Access:https://hdl.handle.net/1721.1/136894
Description
Summary:Abstract Let F be a totally real number field and let f be a classical cuspidal p-regular Hilbert modular eigenform over F of parallel weight 1. Let x be the point on the p-adic Hilbert eigenvariety $${\mathcal {E}}$$ E corresponding to an ordinary p-stabilization of f. We show that if the p-adic Schanuel conjecture is true, then $${\mathcal {E}}$$ E is smooth at x if f has CM. If we additionally assume that $$F/\mathbb {Q}$$ F / Q is Galois, we show that the weight map is étale at x if f has either CM or exotic projective image (which is the case for almost all cuspidal Hilbert modular eigenforms of parallel weight 1). We prove these results by showing that the completed local ring of the eigenvariety at x is isomorphic to a universal nearly ordinary Galois deformation ring.