How to recognize a true Σ^0_3 set

• Autorzy: Etienne Matheron
• Języki publikacji: EN

Abstrakty

EN

Let X be a Polish space, and let $(A_p)_{p∈ω}$ be a sequence of $G_δ$ hereditary subsets of K(X) (the space of compact subsets of X). We give a general criterion which allows one to decide whether $∪_{p∈ω}A _p$ is a true $∑_3^0$ subset of K(X). We apply this criterion to show that several natural families of thin sets from harmonic analysis are true $∑_3^0$.

Kategorie tematyczne

• 43A46: Special sets (thin sets, Kronecker sets, Helson sets, Ditkin sets, Sidon sets, etc.)

• Wydawca: Institute of Mathematics Polish Academy of Sciences
• Czasopismo: Fundamenta Mathematicae
• Rocznik: 1998
• Tom: 158
• Numer: 2
• Strony: 181-194

Daty

wydano

1998

otrzymano

1998-04-15

Twórcy

autor

Etienne Matheron

• Université Bordeaux 1, 351, Cours de la libération, 33405 Talence Cedex, France

Bibliografia

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