STRINGY PRODUCT ON TWISTED ORBIFOLD K-THEORY FOR ABELIAN QUOTIENTS

摘要

In this paper we present a model to calculate the stringy product oil twisted orbifold K-theory of Adem-Ruan-Zhang for abelian complex orbifolds In the first part we consider the non-twisted case oil an orbifold presented as the quotient of a manifold acted by a compact abelian Lie group We give an explicit description of the obstruction bundle, we explain the relation with the product defined by and, via a Chern character map. with the Chen-Ruan cohomology, we explicitly calculate the stringy product for a weighted projective orbifold In the second part we consider orbifolds presented as the quotient; of a manifold acted by a finite abelian group and twistings coming from the group cohomology We show a decomposition formula for twisted orbifold K-theory that, is suited to calculate the stringy product and we use this formula to calculate two examples when the group is (Z/2)(3)