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La singularité de O'Grady

Manfred Lehn·Christoph Sorger
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Abstract

Let M be the moduli space of semistable sheaves with Mukai vector 2v on an abelian or K3 surface where v is primitive such that =2. We show that the blow-up of the reduced singular locus of M provides a symplectic resolution of singularities. This gives a direct description of O'Grady's resolutions of M\_{K3}(2,0,4) and M\_{Ab}(2,0,2).

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Manfred Lehn, Christoph Sorger. 2006-03-30. La singularité de O'Grady. https://arxiv.org/abs/math/0504182

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