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Projective moduli space of semistable principal sheaves for a reductive group

Tomas L. Gomez·Ignacio Sols
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Abstract

Let X be a smooth projective complex variety, and let G be an algebraic reductive complex group. We define the notion of principal G-sheaf, that generalises the notion of principal G-bundle. Then we define a notion of semistability, and construct the projective moduli space of semistable principal G-sheaves on X. This is a natural compactification of the moduli space of principal G-bundles. This is the announcement note presented by the second author in the conference held at Catania (11-13 April 2001), dedicated to the 60th birthday of Silvio Greco. Detailed proofs will appear elsewhere.

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Tomas L. Gomez, Ignacio Sols. 2001-12-11. Projective moduli space of semistable principal sheaves for a reductive group. https://arxiv.org/abs/math/0112096

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