Partial isometries and EP elements in rings with involution
نویسندگان
چکیده
If R is a ring with involution, and a† is the Moore-Penrose inverse of a ∈ R, then the element a is called: EP, if aa† = a†a; partial isometry, if a∗ = a†; star-dagger, if a∗a† = a†a∗. In this paper, characterizations of partial isometries, EP elements and star-dagger elements in rings with involution are given. Thus, some well-known results are extended to more general settings.
منابع مشابه
Ela on Ep Elements, Normal Elements and Partial Isometries in Rings with Involution
This is a continuation to the study of EP elements, normal elements and partial isometries in rings with involution. The aim of this paper is to give the negative solution to three conjectures on this subject. Moreover, some new characterizations of EP elements in rings with involution are presented.
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This is a continuation to the study of EP elements, normal elements and partial isometries in rings with involution. The aim of this paper is to give the negative solution to three conjectures on this subject. Moreover, some new characterizations of EP elements in rings with involution are presented.
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We investigate elements in rings with involution which are EP or partial isometries. Some well-known results are generalized.
متن کاملEla Partial Isometries and Ep Elements in Rings with Involution∗
∗Received by the editors June 1, 2009. Accepted for publication November 12, 2009. Handling Editor: Michael J. Tsatsomeros. †Faculty of Sciences and Mathematics, University of Nǐs, P.O. Box 224, 18000 Nǐs, Serbia ([email protected], [email protected]). Supported by the Ministry of Science, Republic of Serbia, grant no. 144003. Electronic Journal of Linear Algebra ISSN 1081-3810 A publication of the In...
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