On linear operators and functors extending pseudometrics

• Autorzy: C. Bessaga
• Języki publikacji: EN

Abstrakty

EN

For some pairs (X,A), where X is a metrizable topological space and A its closed subset, continuous, linear (i.e., additive and positive-homogeneous) operators extending metrics for A to metrics for X are constructed. They are defined by explicit analytic formulas, and also regarded as functors between certain categories. An essential role is played by "squeezed cones" related to the classical cone construction. The main result: if A is a nondegenerate absolute neighborhood retract for metric spaces, then continuous linear operators extending metrics always exist.

• Wydawca: Institute of Mathematics Polish Academy of Sciences
• Czasopismo: Fundamenta Mathematicae
• Rocznik: 1993
• Tom: 142
• Numer: 2
• Strony: 101-122

Daty

wydano

1993

otrzymano

1991-03-25

poprawiono

1991-12-12

poprawiono

1992-05-12

poprawiono

1992-08-10

Twórcy

autor

C. Bessaga

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

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