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Average of two extreme points in \(JBW^*\)-triples. (English) Zbl 1207.46046

Summary: H. Choda [Proc.Japan Acad.46, 341–344 (1970; Zbl 0207.44402)] proved that every element in the closed unit ball of a von Neumann algebra is the average of two extreme points of the ball. Here, we prove the strict generalization of Choda’s result to arbitrary \(JBW^*\)-triples.

MSC:

46K70 Nonassociative topological algebras with an involution
17C65 Jordan structures on Banach spaces and algebras
46H70 Nonassociative topological algebras
46L70 Nonassociative selfadjoint operator algebras

Citations:

Zbl 0207.44402
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References:

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