ArticleOriginal scientific text
Title
Borel partitions of unity and lower Carathéodory multifunctions
Authors 1
Affiliations
- Stat-Math Unit, Indian Statistical Institute 203 B.T. Road Calcutta 700 035, India
Abstract
We prove the existence of Carathéodory selections and representations of a closed convex valued, lower Carathéodory multifunction from a set A in into a separable Banach space Y, where ℰ is a sub-σ-field of the Borel σ-field ℬ(E) of a Polish space E, X is a Polish space and A is the Suslin operation. As applications we obtain random versions of results on extensions of continuous functions and fixed points of multifunctions. Such results are useful in the study of random differential equations and inclusions and in mathematical economics.
As a key tool we prove that if A is an analytic subset of E × X and if is a sequence of Borel sets in A such that and the section is open in A(e), e ∈ E, n ∈ w, then there exist Borel functions , n ∈ w, such that for every e ∈ E, is a locally Lipschitz partition of unity subordinate to .
Keywords
Carathéodory functions and multifunctions, Carathéodory selections, fixed points
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Additional information
http://matwbn.icm.edu.pl/ksiazki/fm/fm146/fm14633.pdf