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Birational classification of moduli spaces of vector bundles over $\mathbb{P}^{2}$

Aidan Schofield
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Abstract

The depth of a vector bundle E over the projective plane P^2 is the largest integer h such that [E]/h is in the Grothendieck group of coherent sheaves on P^2 where [E] is the class of E in this Grothendieck group. We show that a moduli space of vector bundles is birational to a suitable number of h by h matrices up to simultaneous conjugacy where h is the depth of the vector bundles classified by the moduli space. In particular, such a moduli space is a rational variety if h <= 4 and is stably rational when h divides 420.

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Aidan Schofield. 1999-12-01. Birational classification of moduli spaces of vector bundles over $\mathbb{P}^{2}$. https://arxiv.org/abs/math/9912005

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