The ring structure for equivariant twisted K-theory

  title={The ring structure for equivariant twisted K-theory},
  author={Jean-Louis Tu and Ping Xu},
Abstract We prove, under some mild conditions, that the equivariant twisted K-theory group of a crossed module admits a ring structure if the twisting 2-cocycle is 2-multiplicative. We also give an explicit construction of the transgression map for any crossed module N → Γ and prove that any element in the image is ∞-multiplicative. As a consequence, we prove, under some mild conditions, for a crossed module N → Γ and any , that the equivariant twisted K-theory group admits a ring structure. As… 

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