Automorphisms of moduli spaces of principal bundles over a smooth curve

Roberto Fringuelli

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arXiv · 2112.08750

Automorphisms of moduli spaces of principal bundles over a smooth curve

Roberto Fringuelli

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Abstract

For any almost-simple group $G$ over an algebraically closed field $k$ of characteristic zero, we describe the automorphism group of the moduli space of semistable $G$-bundles over a connected smooth projective curve $C$ of genus at least $4$. The result is achieved by studying the singular fibers of the Hitchin fibration. As a byproduct, we provide a description of the irreducible components of two natural closed subsets in the Hitchin basis: the divisor of singular cameral curves and the divisor of singular Hitchin fibers.

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Roberto Fringuelli. 2021-12-16. Automorphisms of moduli spaces of principal bundles over a smooth curve. https://arxiv.org/abs/2112.08750

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