• Title of article

    Characters of countably tight spaces and inaccessible cardinals

  • Author/Authors

    Usuba، نويسنده , , Toshimichi، نويسنده ,

  • Issue Information
    دوماهنامه با شماره پیاپی سال 2014
  • Pages
    12
  • From page
    95
  • To page
    106
  • Abstract
    In this paper, we study some connections between characters of countably tight spaces of size ω 1 and inaccessible cardinals. A countable tight space is indestructible if every σ-closed forcing notion preserves countable tightness of the space. We show that, assuming the existence of an inaccessible cardinal, the following statements are consistent:(1) indestructibly countably tight space of size ω 1 has character ⩽ ω 1 . > ω 2 and there is no countably tight space of size ω 1 and character ω 2 . he converse, we show that, if ω 2 is not inaccessible in the constructible universe L, then there is an indestructibly countably tight space of size ω 1 and character ω 2 .
  • Keywords
    Countable tight space , Countable tightness indestructibility , Topological game , Kurepa tree , Inaccessible cardinal
  • Journal title
    Topology and its Applications
  • Serial Year
    2014
  • Journal title
    Topology and its Applications
  • Record number

    1584010