Approximation by invertibles

Author:
Michael Gartenberg

Journal:
Proc. Amer. Math. Soc. **61** (1976), 341-346

MSC:
Primary 46L05; Secondary 58D05

MathSciNet review:
0435858

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Abstract | References | Similar Articles | Additional Information

Abstract: The uniform closure of the set of invertibles of certain -algebras is characterized. It is shown that indices on , where is a closed annulus in the plane and on have continuous extensions to elements which are not invertible.

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Additional Information

DOI:
https://doi.org/10.1090/S0002-9939-1976-0435858-X

Keywords:
-algebras,
extensions of indices,
invertible element

Article copyright:
© Copyright 1976
American Mathematical Society