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Singular principal bundles over higher dimensional manifolds and their moduli spaces

Alexander Schmitt
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Abstract

In this note, we introduce the notion of a singular principal G-bundle, associated to a reductive algebraic group G over the complex numbers by means of a faithful representation $\varrho^\p\colon G\lra \SL(V)$. This concept is meant to provide an analogon to the notion of a torsion free sheaf as a generalization of the notion of a vector bundle. We will construct moduli spaces for these singular principal bundles which compactify the moduli spaces of stable principal bundles.

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Alexander Schmitt. 2002-01-10. Singular principal bundles over higher dimensional manifolds and their moduli spaces. https://arxiv.org/abs/math/0201085

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