Numerical radius inequalities for Hilbert space operators 论文
2005Studia Mathematica引用 333
Mathematical Inequalities and ApplicationsMatrix Theory and AlgorithmsSpectral Theory in Mathematical Physics
摘要
It is shown that if $A$ is a bounded linear operator on a complex Hilbert space, then $$ {1 \over 4}\| {A^* A + AA^* } \| \le ( {w(A )} )^2 \le {1 \over 2}\| {A^* A + AA^* }\| , $$ where $w(\cdot )$ and $\| \cdot \| $ are the numerical radius and the u