Linear combinations of projections in von Neumann algebras

Goldstein, Stanisław; Paszkiewicz, Adam

doi:10.1090/S0002-9939-1992-1094501-9

Linear combinations of projections in von Neumann algebras
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by Stanisław Goldstein and Adam Paszkiewicz

Proc. Amer. Math. Soc. 116 (1992), 175-183

DOI: https://doi.org/10.1090/S0002-9939-1992-1094501-9

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Abstract:

Any operator in a von Neumann algebra is a linear combination of a finite number of projections from the algebra with coefficients from the center of the algebra. Those von Neumann algebras that are the complex linear span of their projections are identified.

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