The goal of this paper consists in giving some properties related to the spectrum Sp_P(a, b) of some couples (a, b) in a Banach-Jordan pair  We especially prove that the spectrum multifunction  is upper semi-continuous.

Banach-Jordan pair, Banach-Jordan algebra, spectrum, idempotent.

Received: October 20, 2021; Revised: November 30, 2021; Accepted: December 10, 2021; Published: December 20, 2021

How to cite this article: Hassan Marhnine, Chafika Zarhouti and Mariam Oulad Fares, On some spectrum properties in Banach-Jordan pairs, International J. Functional Analysis, Operator Theory and Applications 13(2) (2021), 67-78. DOI: 10.17654/0975291921001

This Open Access Article is Licensed under Creative Commons Attribution 4.0 International License

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