Hostname: page-component-848d4c4894-nr4z6 Total loading time: 0 Render date: 2024-04-30T12:05:39.909Z Has data issue: false hasContentIssue false

On complemented and annihilator algebras

Published online by Cambridge University Press:  18 May 2009

Freda E. Alexander
Affiliation:
University of Glasgow
Rights & Permissions [Opens in a new window]

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The purpose of this paper is twofold. In [6] Tomiuk gives a representation theorem for a topologically simple right complemented algebra that is also an annihilator algebra. We strengthen this and then give a converse, so as to characterise right complemented algebras among respectively primitive Banach algebras and primitive annihilator Banach algebras. Our second aim is to investigate the relationship between the different annihilator conditions—left annihilator, right annihilator, annihilator, and dual—when imposed on a complemented algebra. Tomiuk [6] has already shown that a right complemented semisimple algebra that is a left annihilator algebra is an annihilator algebra; further, a topologically simple bi-complemented algebra that is also an annihilator algebra is dual. We show that for a topologically simple right complemented algebra all four annihilator conditions are equivalent. Further, for a semi-simple Banach algebra the first three are equivalent provided it is right complemented, and if it is also left complemented, then they are equivalent to duality.

Type
Research Article
Copyright
Copyright © Glasgow Mathematical Journal Trust 1969

References

REFERENCES

1.Bonsall, F. F. and Goldie, A. W., Annihilator algebras, Proc. London Math. Soc. (3) 4 (1954), 154167.Google Scholar
2.Kakutani, S. and Mackey, G. W., Ring and lattice characterisations of complex Hilbert space, Bull. Amer. Math. Soc. (2) 52 (1946), 727733.CrossRefGoogle Scholar
3.Mackey, G. W., Isomorphisms of normed linear spaces, Ann. of Math. 43 (1942), 244260.Google Scholar
4.Rickart, C. E., General theory of Banach algebras (Princeton, 1960).Google Scholar
5.Smiley, M. F., Right annihilator algebras, Proc. Amer. Math. Soc. 6 (1955), 698701.CrossRefGoogle Scholar
6.Tomiuk, B. J., Structure theory of complemented Banach algebras, Canadian J. Math. 14 (1962), 651659.CrossRefGoogle Scholar