Complemented subspaces and amenability: a counterexample
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- by Yuji Takahashi PDF
- Proc. Amer. Math. Soc. 118 (1993), 1113-1115 Request permission
Abstract:
We give an example of a left amenable discrete semigroup $S$ such that ${l^\infty }(S)$ has weak$^{{\ast }}$-closed selfadjoint left translation invariant subalgebras that are weak$^{{\ast }}$-complemented but not invariantly complemented in ${l^\infty }(S)$. This resolves negatively a problem raised by Lau.References
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Additional Information
- © Copyright 1993 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 118 (1993), 1113-1115
- MSC: Primary 43A07; Secondary 43A15
- DOI: https://doi.org/10.1090/S0002-9939-1993-1143024-8
- MathSciNet review: 1143024