Czechoslovak Mathematical Journal, Vol. 70, No. 2, pp. 539-551, 2020


Characterizations of partial isometries and two special kinds of EP elements

Ruju Zhao, Hua Yao, Junchao Wei

Received August 26, 2018.   Published online December 12, 2019.

Abstract:  We give some sufficient and necessary conditions for an element in a ring to be an EP element, partial isometry, normal EP element and strongly EP element by using solutions of certain equations.
Keywords:  EP element; partial isometry; normal EP element; strongly EP element; solutions of equation
Classification MSC:  15A09, 16U99, 16W10


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Affiliations:   Ruju Zhao (corresponding author), Hua Yao , Junchao Wei, School of Mathematical Science, Yangzhou University, 180, Siwangting Road, Hanjiang District, Yangzhou, Jiangsu 225002, P. R. China, e-mail: zrj0115@126.com


 
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