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On moduli spaces of flat connections with non-simply connected structure group

Christoph Schweigert
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Abstract

We consider the moduli space of flat G-bundles over the twodimensional torus, where G is a real, compact, simple Lie group which is not simply connected. We show that the connected components that describe topologically non-trivial bundles are isomorphic as symplectic spaces to moduli spaces of topologically trivial bundles with a different structure group. Some physical applications of this isomorphism which allows to trade topological non-triviality for a change of the gauge group are sketched.

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Christoph Schweigert. 1996-11-12. On moduli spaces of flat connections with non-simply connected structure group. https://doi.org/10.1016/s0550-3213(97)00152-1

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