Memory efficient hyperelliptic curve point counting

Hendrik Hubrechts

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Memory efficient hyperelliptic curve point counting

Hendrik Hubrechts

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Abstract

In recent algorithms that use deformation in order to compute the number of points on varieties over a finite field, certain differential equations of matrices over p-adic fields emerge. We present a novel strategy to solve this kind of equations in a memory efficient way. The main application is an algorithm requiring quasi-cubic time and only quadratic memory in the parameter n, that solves the following problem: for E a hyperelliptic curve of genus g over a finite field of extension degree n and small characteristic, compute its zeta function. This improves substantially upon Kedlaya's result which has the same quasi-cubic time asymptotic, but requires also cubic memory size.

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Hendrik Hubrechts. 2006-09-01. Memory efficient hyperelliptic curve point counting. https://arxiv.org/abs/math/0609032

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