A Complete Obstruction to the Existence of Nonvanishing Vector Fields on Almost-complex, Closed, Cyclic Orbifolds
نویسنده
چکیده
We determine several necessary and sufficient conditions for a closed almost-complex orbifold Q with cyclic local groups to admit a nonvanishing vector field. These conditions are stated separately in terms of the orbifold Euler-Satake characteristics of Q and its sectors, the Euler characteristics of the underlying topological spaces of Q and its sectors, and in terms of the orbifold Euler class eorb(Q) in Chen-Ruan orbifold cohomology H ∗ orb (Q;R).
منابع مشابه
A Complete Obstruction to the Existence of Nonvanishing Vector Fields on Almost-Complex, Closed Orbifolds
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تاریخ انتشار 2008