Hostname: page-component-586b7cd67f-2brh9 Total loading time: 0 Render date: 2024-11-24T03:13:53.888Z Has data issue: false hasContentIssue false

Remarks on completeness in spaces of linear operators

Published online by Cambridge University Press:  17 April 2009

W. Ricker
Affiliation:
School of Mathematics and Physics, Macquarie University, North Ryde, 2113, N.S.W., Australia.
Rights & Permissions [Opens in a new window]

Abstract

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.

Whereas a locally convex Hausdorff space X inherits any completeness properties that the space of continuous linear operators, L (X), in X, may have (for the topology of pointwise convergence in X), this is not so in the converse situation and is the problem discussed here. The barrelledness of X in its Mackey topology plays an important role: if L (X) is quasicomplete, then X is barrelled for its Mackey topology. Consequently, for Mackey spaces X is turns out that L (X) is quasicomplete if and only if X is quasicomplete and barrelled: this is false if sequential completeness is substituted for quasicompleteness. Furthermore, there exist non-barrelled spaces X for which X and L (X) are quasicomplete (sequentially complete). Hence, although barrelledness is a sufficient condition for completeness of L (X) in various senses, it is certainly not necessary.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1986

References

[1]Day, M.M., Normed linear spaces (Ergeb. Math. 21 (2nd printing), Springer, Berlin, (1962).CrossRefGoogle Scholar
[2]Diestel, J. and Uhl, J.J. Jr., Vectro measures (Math. Surveys Monogr. 15 American Mathematical Society, Rhode Island, (1977)).CrossRefGoogle Scholar
[3]Köthe, G., Topological vector spaces I (Grundlehren Math. Wiss. 159 (2nd edition), Springer-Verlag, Berlin-Heidelberg, (1983)).CrossRefGoogle Scholar
[4]Köthe, G., Topological vector spaces II (Grundlehren Math. Wiss. 237 Springer-Verlag, New York, (1979)).CrossRefGoogle Scholar
[5]Schaefer, H.H., Topological vector spaces (Graduate Texts in Math. 3 (4th edition), Springer-Verlag, New York, (1980)).Google Scholar