For more information about this meeting, contact Calder Daenzer, Mathieu Stienon, Nigel Higson, Ping Xu.

Title: | Equivariant K-theory and orbifold power operations |

Seminar: | GAP Seminar |

Speaker: | Takashi Kimura, Boston University |

Abstract: |

Associated to a smooth projective variety X with a proper action of a complex algebraic group G, conditions that insure that the quotient [X/G] is a complex orbifold, is its orbifold K-theory ring, a K-theoretic version of Chen-Ruan orbifold cohomology. Orbifold K-theory contains, as a subring, the ordinary equivariant K-theory of X, and is additively equal to the equivariant K-theory of the inertia manifold of X. In recent work with Edidin and Jarvis,
we show that under certain conditions orbifold K-theory (and its cousins) admit power (or Adams) operations which yields an exotic positive structure (that is, elements which are analogs of classes of vector bundles) on orbifold K-theory. |

### Room Reservation Information

Room Number: | MB106 |

Date: | 03 / 13 / 2012 |

Time: | 02:30pm - 03:30pm |