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Math-Physics Joint Seminar

Tuesday, September 29, 2009 - 2:00pm

Takashi Kimura

Boston University

Location

University of Pennsylvania

DRL 4C2

For any finite group G, we give a representation ring valued Riemann-Hurwitz theorem for certain families of complex curves with G-action. We do so by proving it for the universal G-cover over the moduli space of pointed admissible G-covers. We apply these results to give an alternate definition of orbifold cohomology and to calculate some Gromov-Witten invariants.