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Subordinate and Pseudo-Subordinate Semi-Algebras

Published online by Cambridge University Press:  20 November 2018

Edward J. Barbeau*
Affiliation:
The University of Western Ontario, London
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Throughout this paper E denotes a compact Hausdorff space, which, to avoid trivial complications, is assumed to contain at least two points. C(E), with the uniform norm, is the Banach algebra of all continuous real-valued functions defined on E; C+(E) is the set of those functions in C(E) which take only non-negative values. A subset of C(E) is a wedge if and only if it is closed under addition and multiplication by nonnegative scalars; a semi-algebra is a wedge closed under (pointwise) multiplication. The set C+(E) is a semi-algebra, and all semi-algebras considered in this paper are contained in C+(E). For a subset K of C+(E), the closed wedge (semi-algebra) generated by K is the least closed wedge (semi-algebra) containing K.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1967

References

1. Barbeau, E. J., The principal semi-algebra in a Banach algebra, Trans. Amer. Math. Soc., 120 (1965), 116. Google Scholar
2. Bourbaki, N., Intégration (Paris, 1952, 1956).Google Scholar
3. Choquet, G. and Deny, J., Ensembles semi-réticulés et ensembles réticulés de fonctions continues, J. Math. Pures Appl., 36 (1957), 179189.Google Scholar
4. Day, M. M., Normed linear spaces (Berlin, 1962).Google Scholar
5. Gillman, L. and Jerison, M., Rings of continuous functions (Princeton, 1960).Google Scholar
6. Jurkat, W. B. and Lorentz, G. G., Uniform approximation by polynomials with positive coefficients, Duke Math. J., 28 (1961), 463473.Google Scholar