Expected dimensions of higher-rank Brill-Noether loci

Zhang, Naizhen

doi:10.1090/proc/13542

Expected dimensions of higher-rank Brill-Noether loci
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by Naizhen Zhang PDF

Proc. Amer. Math. Soc. 145 (2017), 3735-3746

Abstract:

In this paper, we prove a new expected dimension formula for certain rank two Brill-Noether loci with fixed special determinant. This answers a question asked by Osserman and also leads to a new and much simpler proof of a theorem in his 2015 work. Our result generalizes the well-known result by Bertram, Feinberg and independently Mukai on expected dimension of rank two Brill-Noether loci with canonical determinant and partially verifies a conjecture (in rank two) of Grzegorczyk and Newstead on coherent systems.

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