Quasinormality and subscalarity of class p-wA(s,t) operators

Kotaro Tanahashi

Abstract


Let $T$ be a bounded linear operator on a complex Hilbert space ${\mathcal H}$ and let $T=U|T|$ be the polar decomposition of $T$.  $T $ is called a class $p$-$wA(s,t)$ operator
 if $(|T^{*}|^{t}|T|^{2s}|T^{*}|^{t})^{\frac{tp}{s+t}}\geq |T^{*}|^{2tp}$ and
$(|T|^{s}|T^{*}|^{2t}|T|^{s})^{\frac{sp}{s+t}}\leq |T|^{2sp}$ where $0 <s, t $ and $0 < p \leq 1$.
We investigate quasinormality and
subscarity of class $p$-$wA(s,t)$ operators.

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References


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