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arXiv · 1512.06258

p-adic variation of unit root L-functions

C. Douglas Haessig·Steven Sperber
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Abstract

Dwork's conjecture, now proven by Wan, states that unit root L-functions "coming from geometry" are p-adic meromorphic. In this paper we study the p-adic variation of a family of unit root L-functions coming from a suitable family of toric exponential sums. In this setting, we find that the unit root L-functions each have a unique p-adic unit root. We then study the variation of this unit root over the family of unit root L-functions. Surprisingly, we find that this unit root behaves similarly to the classical case of families of exponential sums. That is, the unit root is essentially a ratio of A-hypergeometric functions.

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C. Douglas Haessig, Steven Sperber. 2015-12-19. p-adic variation of unit root L-functions. https://doi.org/10.2140/pjm.2017.288.129

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