Cardinal numbers associated with dense pseudocompact, countably compact, and ω-bounded subgroups
نویسندگان
چکیده
منابع مشابه
Pseudocompact Totally Dense Subgroups
It was shown by Dikranjan and Shakhmatov in 1992 that if a compact abelian group K admits a proper totally dense pseudocompact subgroup, then K cannot have a torsion closed Gδ-subgroup; moreover this condition was shown to be also sufficient under LH. We prove in ZFC that this condition actually ensures the existence of a proper totally dense subgroup H of K that contains an ω-bounded dense sub...
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ژورنال
عنوان ژورنال: Topology and its Applications
سال: 1998
ISSN: 0166-8641
DOI: 10.1016/s0166-8641(97)00079-5