Differential geometry of monopole moduli spaces
http://jp.arxiv.org/abs/math/0610295
Singular monopoles were first studied by Kronheimer in [25].
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Here we offer a hyperbolic version of Kronheimer’s work.
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Finally we must point out that singular monopoles have recently been studied by
Kapustin and Witten in [23] as part of their work on the Geometric Langlands Programme.
Although the context of their work is very different to ours, [23] nevertheless provides a further justification for the study of singular monopoles.