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​International Journal of Modern Computation, Information and Communication Technology

ISSN 2581-5954

​March-April 2021, Vol. 4, Issue 3-4, p. 7-12.​​

Numerical radii inequalities for derivations induced by orthogonal projections
I. O. Okwany, N. B. Okelo*, O. Ongati
School of Mathematics and Actuarial Science, Jaramogi Oginga Odinga University of Science and Technology, P. O. Box 210-40601, Bondo-Kenya.
*Corresponding author’s e-mail: bnyaare@yahoo.com

Abstract

Let Hn be a finite dimensional Hilbert space and δP,Q be a generalized derivation induced by the orthogonal projections P and Q. In this study, authors have approximated the norm of δP,Q and showed that δP,Q is bounded and is utmost equal to the sum of norms of P and Q. Authors have also considered the linearity and inequalities of in the context of tensor products. Finally, authors have determined the Hilbert-Schmidt and completely bounded norm inequalities for δP,Q.

Keywords: Hilbert space; Orthogonal projections; Hilbert-Schmidt; Inequalities.

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