Open relations and collectionwise normality

• Autorzy: Gutev V.

Identyfikatory

DOI

10.4064/ba8097-4-2017

• Języki publikacji: EN

Abstrakty

EN

Using the framework of discrete-valued relations, we give a simple proof of a theorem obtained by Stoyan Nedev. This theorem provides a generalisation of an element in the proof of Dowker’s extension theorem, which is essential for constructing continuous selections of set-valued mappings defined on collectionwise normal spaces. Using this relationship, we also give a simple proof of the Dowker’s theorem.

Słowa kluczowe

EN

relation; set-valued mapping; collectionwise normality; extension

• Wydawca: Instytut Matematyczny PAN
• Czasopismo: Bulletin of the Polish Academy of Sciences. Mathematics
• Rocznik: 2017
• Tom: Vol. 65, no. 1
• Strony: 69--79
• Opis fizyczny: Bibliogr. 12 poz.

Twórcy

autor

Gutev V.

• Department of Mathematics, Faculty of Science, University of Malta, Msida MSD 2080, Malta

Bibliografia

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• [9] S. Ĭ. Nedev, Four theorems of E. Michael on continuous selections, B"lgar. Akad. Nauk Izv. Mat. Inst. 15 (1974), 389–393.
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• [12] R. E. Smithson, Subcontinuity for multifunctions, Pacific J. Math. 61 (1975), 283–288.