ArticleOriginal scientific text
Title
The σ-ideal of closed smooth sets does not have the covering property
Authors 1
Affiliations
- Departamento de Matemáticas, Facultad de Ciencias, Universidad de Los Andes, Mérida 5101, Venezuela
Abstract
We prove that the σ-ideal I(E) (of closed smooth sets with respect to a non-smooth Borel equivalence relation E) does not have the covering property. In fact, the same holds for any σ-ideal containing the closed transversals with respect to an equivalence relation generated by a countable group of homeomorphisms. As a consequence we show that I(E) does not have a Borel basis.
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Additional information
http://matwbn.icm.edu.pl/ksiazki/fm/fm150/fm15033.pdf