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Antipodal coincidence sets and stronger forms of connectedness

Published online by Cambridge University Press:  17 April 2009

J.E. Harmse
Affiliation:
Department of Mathematics, University of Auckland, Auckland, New Zealand.
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Abstract

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A new notion of α-connectedness (α-path connectedness) in general topological spaces is introduced and it is proved that for a real-valued function defined on a space with this property, the cardinality of the antipodal coincidence set is at least as large as the cardinal number α. In particular, in linear topological spaces, the antipodal coincidence set of a real-valued function has cardinality at least that of the continuum. This could be regarded as a treatment of some Borsuk-Ulam type results in the setting of general topology.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1985

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