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Banach algebra elements whose spectra intersect R+

Published online by Cambridge University Press:  20 January 2009

F. F. Bonsall
Affiliation:
University of Edinburgh, Edinburgh
A. C. Thompson
Affiliation:
Dalhousie University, Halifax, N.S.
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Let A denote a complex Banach algebra with unit, Inv(A) the set of invertible elements of A, Sp(a) and r(a) the spectrum and spectral radius respectively of an element a of A. Let Γ denote the set of elements of A whose spectra contain non-negative real numbers, i.e.

Type
Research Article
Copyright
Copyright © Edinburgh Mathematical Society 1974

References

REFERENCES

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