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LINEAR SYSTEMS OF GEOMETRICALLY IRREDUCIBLE PLANE CUBICS OVER FINITE FIELDS

Published online by Cambridge University Press:  27 February 2025

SHAMIL ASGARLI
Affiliation:
Department of Mathematics and Computer Science, Santa Clara University, 500 El Camino Real, CA 95053, USA e-mail: sasgarli@scu.edu
DRAGOS GHIOCA*
Affiliation:
Department of Mathematics, University of British Columbia, Vancouver, BC V6T 1Z2, Canada

Abstract

We examine the maximum dimension of a linear system of plane cubic curves whose $\mathbb {F}_q$-members are all geometrically irreducible. Computational evidence suggests that such a system has a maximum (projective) dimension of $3$. As a step towards the conjecture, we prove that there exists a three-dimensional linear system $\mathcal {L}$ with at most one geometrically reducible $\mathbb {F}_q$-member.

Type
Research Article
Copyright
© The Author(s), 2025. Published by Cambridge University Press on behalf of Australian Mathematical Publishing Association Inc.

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