A remark on some inequalities for positive linear maps
Subject Areas : Linear and multilinear algebra; matrix theory
1 - Department of Mathematics, Payame Noor University, Tehran, Iran
2 - Department of Mathematics, Payame Noor University, Tehran, Iran
Keywords: Convex function, $s$-convex function, matrix $s$-convex function, $P$-class function, Jensen's inequality,
Abstract :
The objective of this paper is to reveal that an analogue of Jensen's inequality holds for positive unital linear maps and matrix $s$-convex functions. We prove that the restriction to the matrix $s$-convex functions is not necessary in the case of $2 \times 2$ matrices in some sense.
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