Leray-Schauder principles for condensing multivalued mappings in topological linear spaces

Schöneberg, Rainald

doi:10.1090/S0002-9939-1978-0507320-9

Leray-Schauder principles for condensing multivalued mappings in topological linear spaces
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Proc. Amer. Math. Soc. 72 (1978), 268-270 Request permission

Abstract:

By establishing the existence of an equivalent fixed point problem it is shown without any recourse to degree theory or to the theory of homotopy-extension-theorems that all fixed point theorems of Leray-Schauder type for condensing (single- or multi-valued) mappings in topological linear spaces can immediately be deduced from the corresponding fixed point theorems of Schauder type.

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