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arXiv · 1607.05889

Some mixed character sum identities of Katz

Ronald J. Evans
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Abstract

A conjecture connected with quantum physics led N. Katz to discover some amazing mixed character sum identities over a field of $q$ elements, where $q$ is a power of a prime $p>3$. His proof required deep algebro-geometric techniques, and he expressed interest in finding a more straightforward direct proof. Such a proof has been given by Evans and Greene in the case $q \equiv 3 \pmod 4$, and in this paper we give a proof for the remaining case $q \equiv 1 \pmod 4$. Moreover, we show that the identities are valid for all characteristics $p >2$.

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Ronald J. Evans. 2016-07-20. Some mixed character sum identities of Katz. https://arxiv.org/abs/1607.05889

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