On linear operators extending [pseudo]metrics

• Autorzy: Banach T. , Bessaga C.
• Języki publikacji: EN

Abstrakty

EN

For every closed subset X of a stratifiable [respectively metrizable] space Y we construct a positive linear extension operator T : R[sup X*X] --> R[sup Y*Y] preserving constant functions, bounded functions, continuous functions, pseudometrics, metrics, [respectively dominating metrics, and admissible metrics]. This operator is continuous with respect to each of the three topologies : point-wise convergence, uniform, and compact-open. An equivariant analog of the above statement is proved as well.

Słowa kluczowe

EN

linear extension operator; metric; pseudometric; stratifiable space

PL

Hartman-Mycielski construction.; metryka; operator liniowy; pseudometryka; topologia

• Wydawca: Instytut Matematyczny PAN
• Czasopismo: Bulletin of the Polish Academy of Sciences. Mathematics
• Rocznik: 2000
• Tom: Vol. 48, no 1
• Strony: 35--49
• Opis fizyczny: Bibliogr. 16 poz.,

Twórcy

autor

Banach T.

• Department of Mathematics, Lviv University, Universytetska 1, Lviv, 290602, Ukraine

autor

Bessaga C.

• Institute of Mathematics, Warsaw University, Banacha 2, 02-097 Warszawa, Poland

Bibliografia

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