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arXiv · 1503.03049

On a conjecture of Tsfasman and an inequality of Serre for the number of points on hypersurfaces over finite fields

Mrinmoy Datta·Sudhir R. Ghorpade
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Abstract

We give a short proof of an inequality, conjectured by Tsfasman and proved by Serre, for the maximum number of points on hypersurfaces over finite fields. Further, we consider a conjectural extension, due to Tsfasman and Boguslavsky, of this inequality to an explicit formula for the maximum number of common solutions of a system of linearly independent multivariate homogeneous polynomials of the same degree with coefficients in a finite field. This conjecture is shown to be false, in general, but is also shown to hold in the affirmative in a special case. Applications to generalized Hamming weights of projective Reed-Muller codes are outlined and a comparison with an older conjecture of Lachaud and a recent result of Couvreur is given.

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Mrinmoy Datta, Sudhir R. Ghorpade. 2015-03-10. On a conjecture of Tsfasman and an inequality of Serre for the number of points on hypersurfaces over finite fields. https://arxiv.org/abs/1503.03049

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