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Vector bundles near negative curves: moduli and local Euler characteristic

Edoardo Ballico·Elizabeth Gasparim·Thomas Köppe
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Abstract

We study moduli spaces of vector bundles on a two-dimensional neighbourhood $Z_k$ of an irreducible curve $\ell = CP^1$ with $\ell^2 = -k$ and give an explicit construction of these moduli as stratified spaces. We give sharp bounds for the local holomorphic Euler characteristic of bundles on $Z_k$ and prove existence of families of bundles with prescribed numerical invariants. Our numerical calculations are performed using a Macaulay 2 algorithm, which is available for download at http://www.maths.ed.ac.uk/~s0571100/Instanton/ .

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Edoardo Ballico, Elizabeth Gasparim, Thomas Köppe. 2009-09-03. Vector bundles near negative curves: moduli and local Euler characteristic. https://doi.org/10.1080/00927870802562351

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