Countable ultraproducts without CH
نویسندگان
چکیده
منابع مشابه
CH and first countable , countably compact spaces ✩
We show that it is consistent with the Continuum Hypothesis that first countable, countably compact spaces with no uncountable free sequences are compact. As a consequence, we get that CH does not imply the existence of a perfectly normal, countably compact, non-compact space, answering a question of Nyikos (Question 287 in the numbering of van Mill and Reed, Open Problems in Topology, Elsevier...
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ژورنال
عنوان ژورنال: Annals of Pure and Applied Logic
سال: 1988
ISSN: 0168-0072
DOI: 10.1016/0168-0072(88)90048-6