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arXiv · 2004.07587

Serre weights and the Breuil-Mézard conjecture for modular forms

Hanneke Wiersema
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Abstract

Serre's strong conjecture, now a theorem of Khare and Wintenberger, states that every two-dimensional continuous, odd, irreducible mod $p$ Galois representation $ρ$ arises from a modular form of a specific minimal weight $k(ρ)$, level $N(ρ)$ and character $ε(ρ)$. In this short paper we show that the minimal weight $k(ρ)$ is equal to a notion of minimal weight inspired by the recipe for weights introduced by Buzzard, Diamond and Jarvis. Moreover, using the Breuil-Mézard conjecture we show that both weight recipes are equal to the smallest $k \geq 2$ such that $ρ$ has a crystalline lift of Hodge-Tate type $(0,k-1)$.

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BibTeXRIS

Hanneke Wiersema. 2020-04-16. Serre weights and the Breuil-Mézard conjecture for modular forms. https://arxiv.org/abs/2004.07587

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