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arXiv · 1010.4060

The maximal rank conjecture and rank two Brill-Noether theory

Gavril Farkas·Angela Ortega
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Abstract

We describe applications of Koszul cohomology to the Brill-Noether theory of rank 2 vector bundles. Among other things, we show that in every genus g>10, there exist curves invalidating Mercat's Conjecture for rank 2 bundles. On the other hand, we prove that Mercat's Conjecture holds for general curves of bounded genus, and its failure locus is a Koszul divisor in the moduli space of curves. We also formulate a conjecture concerning the minimality of Betti diagrams of suitably general curves, and point out its consequences to rank 2 Brill-Noether theory.

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Gavril Farkas, Angela Ortega. 2010-12-22. The maximal rank conjecture and rank two Brill-Noether theory. https://arxiv.org/abs/1010.4060

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