Geodesic
The Structure of C *-Convex Sets
Canadian journal of mathematics, Tome 46 (1994) no. 5, pp. 1007-1026

Voir la notice de l'article provenant de la source Cambridge University Press

Compact C *-convex subsets of M n correspond exactly to n-th matrix ranges of operators. The main result of this paper is to discover the “right” analog of linear extreme points, called structural elements, and then to prove a generalised Krein-Milman theorem for C *-convex subsets of M n. The relationship between structural elements and an earlier attempted generalisation, called C *-extreme points, is examined,solving affirmatively a conjecture of Loebl and Paulsen [8]. An improved bound for a C * -convex version of the Caratheodory theorem for convex sets is also given.
DOI : 10.4153/CJM-1994-058-0
Mots-clés : 47A12, 15A30, 52A01 
Morenz, Phillip B. The Structure of C *-Convex Sets. Canadian journal of mathematics, Tome 46 (1994) no. 5, pp. 1007-1026. doi: 10.4153/CJM-1994-058-0
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