Glasnik Matematicki, Vol. 56, No. 1 (2021), 151-162.

ANGULAR RIGHT SYMMETRICITY OF BOUNDED LINEAR OPERATORS ON HILBERT SPACES

Seyed Mohammad Sadegh Nabavi Sales

Department of Mathematics and Computer Sciences, Hakim Sabzevari University, P.O. Box 397, Sabzevar, Iran
e-mail: sadegh.nabavi@gmail.com & sadegh.nabavi@hsu.ac.ir

Abstract.   We introduce and characterize angular right symmetric and approximate angular right symmetric points of the algebra of all bounded linear operators defined on either real or complex Hilbert spaces.

2020 Mathematics Subject Classification.   47B49, 46C05, 46B20

Key words and phrases.   Angle in normed spaces, Birkhoff-James orthogonality, right symmetric points, angular right symmetric points

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https://doi.org/10.3336/gm.56.1.09

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