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Slopes of overconvergent 2-adic modular forms

Kevin Buzzard·Frank Calegari
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Abstract

The slope of a p-adic overconvergent eigenform of weight k is the p-adic valuation of its U_p eigenvalue. We find the slope of all 2-adic finite slope overconvergent eigenforms of tame level 1 and weight 0. As a consequence we prove that any finite slope 2-adic overconvergent eigenform of tame level 1 and weight 0 has coefficients in Q_2. These results provide evidence towards conjectures of the first author that predict the slopes of classical p-adic modular forms under a mild ``Gamma_0(N)''-regular hypothesis on p.

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Kevin Buzzard, Frank Calegari. 2003-11-20. Slopes of overconvergent 2-adic modular forms. https://arxiv.org/abs/math/0311364

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