A Complete Obstruction to the Existence of Nonvanishing Vector Fields on Almost-Complex, Closed Orbifolds
نویسنده
چکیده
We determine several necessary and sufficient conditions for a closed almost-complex orbifold Q to admit a nonvanishing vector field. These conditions are stated separately in terms of the orbifold Euler-Satake characteristics of Q and the connected components of its twisted sectors, the Euler characteristics of the underlying topological spaces of Q and the components of its twisted sectors, and in terms of the orbifold Euler class eorb(Q) in Chen-Ruan orbifold cohomology H ∗ orb(Q;R).
منابع مشابه
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تاریخ انتشار 2009