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The distance between unitary orbits of normal elements in the Calkin algebra

Published online by Cambridge University Press:  14 November 2011

Kenneth R. Davidson
Kenneth R. Davidson
Affiliation:
Pure Mathematics Department, University of Waterloo, Waterloo, Ontario, Canada N2L3G1
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Extract

Let s and t be normal elements of the Calkin algebra, and let (s) denote the unitary orbit of s. A formula ρ(s,t) is defined to measure the distance between unitary orbits, and satisfies

Type
Research Article
Information
Proceedings of the Royal Society of Edinburgh Section A: Mathematics , Volume 99 , Issue 1-2 , 1984 , pp. 35 - 43
Copyright
Copyright © Royal Society of Edinburgh 1984

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