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arXiv · 1612.04237

Producing Geometric Deformations of Orthogonal and Symplectic Galois Representations

Jeremy Booher
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Abstract

For a representation of the absolute Galois group of the rationals over a finite field of characteristic $p$, we study the existence of a lift to characteristic zero that is geometric in the sense of the Fontaine-Mazur conjecture. For two-dimensional representations, Ramakrishna proved that under technical assumptions odd representations admit geometric lifts. We generalize this to higher dimensional orthogonal and symplectic representations. A key step is generalizing and studying a local deformation condition at $p$ arising from Fontaine-Laffaille theory.

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Jeremy Booher. 2018-07-27. Producing Geometric Deformations of Orthogonal and Symplectic Galois Representations. https://doi.org/10.1016/j.jnt.2018.05.022

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