Orbit Projections as Fibrations
نویسنده
چکیده
The orbit projection π :M →M/G of a proper G-manifold M is a fibration if and only if all points inM are regular. Under additional assumptions we show that π is a quasifibration if and only if all points are regular. We get a full answer in the equivariant category: π is a G-quasifibration if and only if all points are regular.
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