Some Inequalities for (α, Β)-normal Operators in Hilbert Spaces

نویسنده

  • SEVER S. DRAGOMIR
چکیده

An operator T is called (α, β)-normal (0 ≤ α ≤ 1 ≤ β) if αT ∗T ≤ TT ∗ ≤ βT ∗T. In this paper, we establish various inequalities between the operator norm and its numerical radius of (α, β)-normal operators in Hilbert spaces. For this purpose, we employ some classical inequalities for vectors in inner product spaces.

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تاریخ انتشار 2008