Cuntz-Krieger-Pimsner algebras associated with amalgamated free product groups

  title={Cuntz-Krieger-Pimsner algebras associated with amalgamated free product groups},
  author={Rui Okayasu},
  journal={Publications of The Research Institute for Mathematical Sciences},
  • Rui Okayasu
  • Published 10 October 2000
  • Mathematics
  • Publications of The Research Institute for Mathematical Sciences
We give a construction of a nuclear C*-algebra associated with an amalgamated free product of groups, generalizing Spielberg's construction of a certain Cuntz-Krieger algebra associated with a finitely generated free product of cyclic groups. Our nuclear C*-algebras can be identified with certain Cuntz-Krieger-Pimsner algebras. We will also show that our algebras can be obtained by the crossed product construction of the canonical actions on the hyperbolic boundaries, which proves a special… 
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