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Relations between two inequalities\((B^{\tfrac{r}{2}} A^p B^{\tfrac{r}{2}} )^{\tfrac{r}{{p + r}}} \geqslant B^r andA^p \geqslant (A^{\tfrac{p}{2}} B^r A^{\tfrac{p}{2}} )^{\tfrac{p}{{p + r}}}\) and their applications

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Abstract

LetA andB be positive invertible operators. Then for eachp≥0 andr≥0, two inequalities

$$(B^{\tfrac{r}{2}} A^p B^{\tfrac{r}{2}} )^{\tfrac{r}{{p + r}}} \geqslant B^r andA^p \geqslant (A^{\tfrac{p}{2}} B^r A^{\tfrac{p}{2}} )^{\tfrac{p}{{p + r}}}$$

are equivalent. In this paper, we shall show relations between these inequalities in caseA andB are not invertible. And we shall show some applications of this result to operator classes.

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Ito, M., Yamazaki, T. Relations between two inequalities\((B^{\tfrac{r}{2}} A^p B^{\tfrac{r}{2}} )^{\tfrac{r}{{p + r}}} \geqslant B^r andA^p \geqslant (A^{\tfrac{p}{2}} B^r A^{\tfrac{p}{2}} )^{\tfrac{p}{{p + r}}}\) and their applications. Integr equ oper theory 44, 442–450 (2002). https://doi.org/10.1007/BF01193670

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  • DOI: https://doi.org/10.1007/BF01193670

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