A category Ψ-density topology

• Autorzy: Władysław Wilczyński , Wojciech Wojdowski
• Języki publikacji: EN

Abstrakty

EN

Ψ-density point of a Lebesgue measurable set was introduced by Taylor in [Taylor S.J., On strengthening the Lebesgue Density Theorem, Fund. Math., 1958, 46, 305–315] and [Taylor S.J., An alternative form of Egoroff’s theorem, Fund. Math., 1960, 48, 169–174] as an answer to a problem posed by Ulam. We present a category analogue of the notion and of the Ψ-density topology. We define a category analogue of the Ψ-density point of the set A at a point x as the Ψ-density point at x of the regular open representation of A.

Słowa kluczowe

EN

Density point; Density topology

Kategorie tematyczne

• 54A10: Several topologies on one set (change of topology, comparison of topologies, lattices of topologies)
• 28A05: Classes of sets (Borel fields, σ -rings, etc.), measurable sets, Suslin sets, analytic sets

• Wydawca: De Gruyter Open
• Czasopismo: Open Mathematics
• Rocznik: 2011
• Tom: 9
• Numer: 5
• Strony: 1057-1066

Daty

wydano

2011-10-01

online

2011-07-26

Twórcy

autor

Władysław Wilczyński

• University of Łódź

autor

Wojciech Wojdowski

• Technical University of Łódź

Bibliografia

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Identyfikatory

DOI

10.2478/s11533-011-0069-0