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Proceedings of the Estonian Academy of Sciences

ISSN 1736-7530 (electronic)   ISSN 1736-6046 (print)
Formerly: Proceedings of the Estonian Academy of Sciences, series Physics & Mathematics and  Chemistry
Published since 1952

Proceedings of the Estonian Academy of Sciences

ISSN 1736-7530 (electronic)   ISSN 1736-6046 (print)
Formerly: Proceedings of the Estonian Academy of Sciences, series Physics & Mathematics and  Chemistry
Published since 1952
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Operator convex functions over C *-algebras; pp. 48–52

(Full article in PDF format) doi: 10.3176/proc.2010.1.08


Authors

Sergei Silvestrov, Hiroyuki Osaka, Jun Tomiyama

Abstract

In this short note we give an exact characterization of C *-algebras that have the class of convex functions. More precisely, we give a convexity characterization of subhomogeneous C *-algebras. We use these results to generalize the single function based convexity conditions for commutativity of a C *-algebra to the single function based convexity conditions for subhomogeneity.

Keywords

operator monotone functions, operator convex functions, matrix convex functions.

References

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  9. Osaka , H. , Silvestrov , S. , and Tomiyama , J. Monotone operator functions on C^*-algebras. Int. J. Math. , 2005 , 16(2) , 181–196.
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Current Issue: Vol. 68, Issue 4, 2019




Publishing schedule:
No. 1: 20 March
No. 2: 20 June
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