@article{1186.47014, author="Seo, Yuki", title="{On a reverse of Ando-Hiai inequality.}", language="English", journal="Banach J. Math. Anal. ", volume="4", number="1", pages="87-91", year="2010", abstract="{Summary: We show a complement of the Ando-Hiai inequality: Let $A$ and $B$ be positive invertible operators on a Hilbert space $H$ and $\alpha\in[0,1]$. If $A\sharp_\alpha B\le I$, then $$A^r\sharp_\alpha B^r\le \|(A\sharp_\alpha B)^{-1}\|^{1-r}I \quad\text{for all }0<r\le 1,$$ where $I$ is the identity operator and $\|\cdot\|$ stands for the operator norm.}", keywords="{Ando-Hiai inequality; positive operator; geometric mean}", classmath="{*47A63 (Operator inequalities, etc.) 47A30 (Operator norms and inequalities) 47A64 (Operator means etc.) }", }