Resumen de The completely bounded approximation property for extended Cuntz--Pimsner algebras

Kenneth J. Dykema, Roger R. Smith

• The extended Cuntz-Pimsner algebra E(H), introduced by Pimsner, is constructed from a Hilbert B,B-bimodule H over a C*-algebra B. In this paper we investigate the Haagerup Lambda invariant for these algebras, the main result being that the value of this invariant for E(H) equals that for B whenever H is full over B. In particular, E(H) has the completely bounded approximation property if and only if the same is true for B.