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On the homotopy property of degree for multivalued noncompact maps

Published online by Cambridge University Press:  18 May 2009

J. R. L. Webb
J. R. L. Webb
Affiliation:
Department of Mathematics, Indiana University, Bloomington, Indiana 47405
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Over the last few years, various extensions of the topological degree of a mapping have been made so as to include non-compact perturbations of the identity. One such extension, which employs compactness conditions, has been to the class of limit compact maps which were extensively studied by Sadovsky [7]. The class is a large one as it contains all compact mappings, contraction mappings and, more generally, condensing mappings. Sadovsky [7] gives a theory of degree for maps of the form I-f, where f is limit compact, and this was extended independently and with different methods by Petryshyn and Fitzpatrick [4] and the author [9] to allow f to be a multi-valued mapping. A refinement of the methods of [9] was given by Vanderbauwhede [8].

Type
Research Article
Information
Glasgow Mathematical Journal , Volume 21 , Issue 1 , January 1980 , pp. 125 - 130
Copyright
Copyright © Glasgow Mathematical Journal Trust 1980

References

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