Finite monodromy of some families of exponential sums

Antonio Rojas-Leon

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arXiv · 1711.01584

Finite monodromy of some families of exponential sums

Antonio Rojas-Leon

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Abstract

Given a prime $p$ and an integer $d>1$, we give a numerical criterion to decide whether the $\ell$-adic sheaf associated to the one-parameter exponential sums $t\mapsto \sum_x\psi(x^d+tx)$ over ${\mathbb F}_p$ has finite monodromy or not, and work out some explicit cases where this is computable.

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Antonio Rojas-Leon. 2017-11-05. Finite monodromy of some families of exponential sums. https://arxiv.org/abs/1711.01584

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