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The Nilpotent Regular Element Problem

Published online by Cambridge University Press:  20 November 2018

Pere Ara
Affiliation:
Department of Mathematics, Universitat Autònoma de Barcelona, 08193 Bellaterra (Barcelona), Spain e-mail: [email protected]
Kevin C. O'Meara
Affiliation:
2901 Gough Street, Apartment 302, San Francisco, CA 94123, USA e-mail: [email protected]
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Abstract

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We use George Bergman's recent normal form for universally adjoining an inner inverse to show that, for general rings, a nilpotent regular element $x$ need not be unit-regular. This contrasts sharply with the situation for nilpotent regular elements in exchange rings (a large class of rings), and for general rings when all powers of the nilpotent element $x$ are regular.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 2016

References

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