## Refinements and reverses of means inequalities for Hilbert space operators.(English)Zbl 1276.47021

This paper discusses improvements of a series of inequalities for Hilbert space operators.
The authors define a functional that measures the difference between the classical arithmetic and geometric means and also deduce some significant scalar inequalities. Section 3 provides, under certain conditions, improvements of the series of inequalities and establishes the lower bound for the difference between the arithmetic and geometric operator means. As an application, in Section 4, the authors establish an improved variant of an inequality concerning the Heinz operator mean. In the final section, the authors present some eigenvalue inequalities for differences of certain operator means.

### MSC:

 47A63 Linear operator inequalities 47A10 Spectrum, resolvent 47B06 Riesz operators; eigenvalue distributions; approximation numbers, $$s$$-numbers, Kolmogorov numbers, entropy numbers, etc. of operators 47B07 Linear operators defined by compactness properties 47B15 Hermitian and normal operators (spectral measures, functional calculus, etc.) 26D20 Other analytical inequalities
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### References:

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