Decomposition of positive projections onto Jordan algebras

Robertson, A. Guyan

doi:10.1090/S0002-9939-1986-0822444-9

Decomposition of positive projections onto Jordan algebras
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by A. Guyan Robertson

Proc. Amer. Math. Soc. 96 (1986), 478-480

DOI: https://doi.org/10.1090/S0002-9939-1986-0822444-9

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Abstract:

If a positive projection $P$ from a ${C^*}$-algebra onto a Jordan algebra can be decomposed as a sum of maps satisfying certain inequalities of the Schwarz type, then $P$ is actually a sum of completely positive and completely copositive maps.

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