Perfect independent sets with respect to infinitely many relations

0463607 - MÚ 2017 RIV DE eng J - Článek v odborném periodiku
Doležal, Martin - Kubiś, Wieslaw
Perfect independent sets with respect to infinitely many relations.
Archive for Mathematical Logic. Roč. 55, č. 7 (2016), s. 847-856. ISSN 0933-5846. E-ISSN 1432-0665
Grant CEP: GA ČR(CZ) GA14-07880S
Institucionální podpora: RVO:67985840
Klíčová slova: perfect clique * free subgroup * open relation
Kód oboru RIV: BA - Obecná matematika
Impakt faktor: 0.394, rok: 2016
http://link.springer.com/article/10.1007%2Fs00153-016-0498-3

We prove a result on perfect cliques with respect to countably many Gdelta relations on a complete metric space. As an application, we show that a Polish group contains a free subgroup generated by a perfect set as long as it contains any uncountable free subgroup. This answers a recent question of Głab and Strobin.
Trvalý link: http://hdl.handle.net/11104/0262750