A Local-Global Study of Obstructed Deformation Problems -- I

Bartu Bingol

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arXiv · 2404.01414

A Local-Global Study of Obstructed Deformation Problems -- I

Bartu Bingol

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Abstract

We study obstructed deformation problems for two-dimensional residual Galois representations arising from weight~$2$ newforms of level~$N$. Using Poitou-Tate duality, we isolate local and global sources of obstructions and give concrete criteria for when they occur. In several cases we also describe the resulting universal deformation ring explicitly.

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Bartu Bingol. 2024-04-01. A Local-Global Study of Obstructed Deformation Problems -- I. https://arxiv.org/abs/2404.01414

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