%0 Book Section %T Point Counting on Non-Hyperelliptic Genus 3 Curves with Automorphism Group $\mathbb{Z} / 2 \mathbb{Z}$ using Monsky-Washnitzer Cohomology %+ Institut de Mathématiques de Marseille (I2M) %A Shieh, Yih-Dar %Z 17 pages. Published in Algorithmic Arithmetic, Geometry, and Coding Theory, Contemporary Mathematics, vol. 637, Amer. Math. Soc., Providence, RI, 2015, pp. 173-189 %@ 978-1-4704-1461-0 %B Algorithmic Arithmetic, Geometry, and Coding Theory %I Amer. Math. Soc., Providence, RI %S Contemporary Mathematics %V 637 %P 173--189 %8 2015 %D 2015 %Z 1603.00566 %R 10.1090/conm/637/12757 %Z 11G05; 11G40 %Z Mathematics [math]/Algebraic Geometry [math.AG]Book sections %X We describe an algorithm to compute the zeta function of any non-hyperelliptic genus 3 plane curve $C$ over a finite field with automorphism group $G = \mathbb{Z} / 2 \mathbb{Z}$. This algorithm computes in the Monsky-Washnitzer cohomology of~the curve. Using the relation between the Monsky-Washnitzer cohomology of $C$ and its quotient $E := C/G$, the computation splits into 2 parts: one in a subspace of the Monsky-Washnitzer cohomology and a second which reduces to the point counting on an elliptic curve $E$. The former corresponds to the dimension $2$ abelian surface $\mathrm{ker}(\mathrm{Jac}(C) \rightarrow E)$, on which we can compute with lower precision and with matrices of smaller dimension. Hence we obtain a faster algorithm than working directly on the curve $C$. %G English %L hal-01321844 %U https://hal.science/hal-01321844 %~ CNRS %~ UNIV-AMU %~ EC-MARSEILLE %~ I2M %~ I2M-2014- %~ ANR