Geodesic
On unitary convex decompositions of vectors in a $JB^{*}$-algebra
Archivum mathematicum, Tome 49 (2013) no. 2, pp. 79-86

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By exploiting his recent results, the author further investigates the extent to which variation in the coefficients of a unitary convex decomposition of a vector in a unital $JB^{*}$-algebra permits the vector decomposable as convex combination of fewer unitaries; certain $ C^{*}$-algebra results due to M. Rørdam have been extended to the general setting of $JB^{*}$-algebras.
By exploiting his recent results, the author further investigates the extent to which variation in the coefficients of a unitary convex decomposition of a vector in a unital $JB^{*}$-algebra permits the vector decomposable as convex combination of fewer unitaries; certain $ C^{*}$-algebra results due to M. Rørdam have been extended to the general setting of $JB^{*}$-algebras.
DOI : 10.5817/AM2013-2-79
Classification : 17C65, 46H70, 46L70
Keywords: $C^{*}$-algebra; $JB^{*}$-algebra; unit ball; invertible element; unitary element; unitary isotope; convex hull; unitary rank; unitary convex decomposition 
Siddiqui, Akhlaq A. On unitary convex decompositions of vectors in a $JB^{*}$-algebra. Archivum mathematicum, Tome 49 (2013) no. 2, pp. 79-86. doi: 10.5817/AM2013-2-79
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