• Title of article

    Topological groups in which all countable subgroups are closed

  • Author/Authors

    Tkachenko، نويسنده , , Mikhail، نويسنده ,

  • Issue Information
    دوماهنامه با شماره پیاپی سال 2012
  • Pages
    9
  • From page
    1806
  • To page
    1814
  • Abstract
    We study the class CC of topological Abelian groups G such that all countable subgroups of G are closed. It is shown that all countably compact subsets of a bounded torsion group in CC are finite, while in general countably compact subsets of any group in CC are countable and compact. proved by the author in 1992 that there exist arbitrarily big pseudocompact groups in CC ; however all these groups did not contain non-trivial convergent sequences. For every infinite cardinal κ satisfying κ ω = κ , we construct here a pseudocompact Abelian group G ∈ CC of cardinality κ which contains non-trivial convergent sequences. w, however, that all countably pseudocompact groups as well as all countably pracompact groups in the class CC are finite.
  • Keywords
    Countably compact , COMPACT , Countably pracompact , Pseudocompact , Reflexive , Convergent sequence , Dual group
  • Journal title
    Topology and its Applications
  • Serial Year
    2012
  • Journal title
    Topology and its Applications
  • Record number

    1583353