Weak expectations and injectivity in operator algebras

Blackadar, Bruce E.

doi:10.1090/S0002-9939-1978-0467329-0

Weak expectations and injectivity in operator algebras
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by Bruce E. Blackadar PDF

Proc. Amer. Math. Soc. 68 (1978), 49-53 Request permission

Abstract:

An example is given of a noninjective von Neumann algebra M on a separable Hilbert space $\mathcal {H}$ for which there exists a weak expectation of $\mathcal {L}(\mathcal {H})$ into M. Some positive results about weak expectations are also obtained.

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Weak expectations and nuclear

algebras

Simple

algebras generated by isometries