Exceptional Discrete Mapping Class Group Orbits in Moduli Spaces
نویسنده
چکیده
Let M be a four-holed sphere and Γ the mapping class group of M fixing ∂M . The group Γ acts on the space MB(SU(2)) of SU(2)-gauge equivalence classes of flat SU(2)-connections on M with fixed holonomy on ∂M . We give examples of flat SU(2)connections whose holonomy groups are dense in SU(2), but whose Γ-orbits are discrete in MB(SU(2)). This phenomenon does not occur for surfaces with genus greater than zero.
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