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Compactness and connectedness as composable properties

Published online by Cambridge University Press:  09 April 2009

T. B. Muenzenberger
Affiliation:
University of Wyoming, Laramie, Wyoming, USA
R. E. Smithson
Affiliation:
University of Wyoming, Laramie, Wyoming, USA
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In [5] Magill showed that compactness is a composable property of Hausdorff spaces. (That is, if α,β are compact subsets of X × X, then α ○ β is also compact when X is T2.) Also Magill gave an example to show that the composition of connected relations need not be connected. Subsequently, he characterized Hausdorff k-spaces in terms of the semigroup of compact relations in X.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1974

References

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