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arXiv · 1801.07754

Reduction of certain crystalline representations and local constancy in the weight space

Shalini Bhattacharya
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Abstract

We study the mod $p$ reduction of crystalline local Galois representations of dimension 2 under certain conditions on its weight and slope. Berger showed that for a fixed non-zero trace of the Frobenius, the reduction process is locally constant for varying weights. By explicit computation we obtain an upper bound that is a linear function of the slope, for the radius of this local constancy around some special points in the weight space.

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Shalini Bhattacharya. 2018-01-23. Reduction of certain crystalline representations and local constancy in the weight space. https://arxiv.org/abs/1801.07754

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