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Relations approximated by continuous functions
Author(s):
L'.
Holá;
R.
A.
McCoy
Journal:
Proc. Amer. Math. Soc.
133
(2005),
2173-2182.
MSC (2000):
Primary 54C35, 54B20, 54C08
Posted:
February 15, 2005
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Additional information
Abstract:
Let be a Tychonoff space, let be the space of all continuous real-valued functions defined on and let be the hyperspace of all nonempty closed subsets of . We prove the following result. Let be a locally connected, countably paracompact, normal -space without isolated points, and let . Then is in the closure of in with the locally finite topology if and only if is the graph of a cusco map. Some results concerning an approximation in the Vietoris topology are also given.
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Additional Information:
L'.
Holá
Affiliation:
Mathematical Institute, Slovak Academy of Sciences, Stefánikova 49, 814 73 Bratislava, Slovakia
Email:
hola@mat.savba.sk
R.
A.
McCoy
Affiliation:
Department of Mathematics, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061
Email:
mccoy@math.vt.edu
DOI:
10.1090/S0002-9939-05-07793-2
PII:
S 0002-9939(05)07793-2
Keywords:
Set-valued mapping,
Vietoris topology,
locally finite topology,
upper-semicontinuous multifunction,
usco map,
cusco map
Received by editor(s):
October 14, 2003
Received by editor(s) in revised form:
April 8, 2004
Posted:
February 15, 2005
Communicated by:
Alan Dow
Copyright of article:
Copyright
2005,
American Mathematical Society
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