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arXiv · 1511.08122

A survey of the GIT picture for the Yang-Mills equation over Riemann surfaces

Samuel Trautwein
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Abstract

The purpose of this paper is to give a self-contained exposition of the Atiyah-Bott picture for the Yang-Mills equation over Riemann surfaces with an emphasis on the analogy to finite dimensional geometric invariant theory. The main motivation is to provide a careful study of the semistable and unstable orbits: This includes the analogue of the Ness uniqueness theorem for Yang-Mills connections, the Kempf-Ness theorem, the Hilbert-Mumford criterion and a new proof of the moment-weight inequality following an approach outlined by Donaldson. A central ingredient in our discussion is the Yang-Mills flow for which we assume longtime existence and convergence.

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Samuel Trautwein. 2015-12-11. A survey of the GIT picture for the Yang-Mills equation over Riemann surfaces. https://arxiv.org/abs/1511.08122

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