On additive almost continuous functions under CPAgame/prism

• Autorzy: Ciesielski K. , Pawlikowski J.
• Języki publikacji: EN

Abstrakty

EN

We prove that the Covering Property Axiom CPAgame/prism, which holds in the iterated perfect set model, implies that there ex-ists an additive discontinuous almost continuous function f : R -> R whose graph is of measure zero. We also show that, under CPAgame/prism, there exists a Hamel basis H for which. E+(H), the set of all linear combinations of elements from H with positive rational coefficients, is of measure zero. The existence of both of these examples follows from Martin's axiom. while it is unknown whether either of them can be constructed in ZFC. As a tool for the constructions we will show that CPAgame/prism implies its seemingly stronger version, in which ω-many games are played simultaneously.

Słowa kluczowe

EN

additive; almost continuous; Hamel basis; Covering Property Axiom; CPA

• Wydawca: De Gruyter
• Czasopismo: Journal of Applied Analysis
• Rocznik: 2005
• Tom: Vol. 11, nr 2
• Strony: 153--170
• Opis fizyczny: Bibliogr. 17 poz.

Twórcy

autor

Ciesielski K.

• Department of Mathematics, West Virginia University, Morgantown, WV 26506-6310, USA

autor

Pawlikowski J.

• Department of Mathematics, University of Wroclaw, pl. Grunwaldzki 2/4, 50-384 Wroclaw, Poland

Bibliografia

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