• Title of article

    What is a first countable space?

  • Author/Authors

    Gutierres، نويسنده , , Gonçalo، نويسنده ,

  • Issue Information
    دوماهنامه با شماره پیاپی سال 2006
  • Pages
    10
  • From page
    3420
  • To page
    3429
  • Abstract
    The definition of first countable space is standard and its meaning is very clear. But is that the case in the absence of the Axiom of Choice? The answer is negative because there are at least three choice-free versions of first countability. And, most likely, the usual definition does not correspond to what we want to be a first countable space. The three definitions as well as other characterizations of first countability are presented and it is discussed under which set-theoretic conditions they remain equivalent.
  • Keywords
    First countable space , AXIOM OF CHOICE
  • Journal title
    Topology and its Applications
  • Serial Year
    2006
  • Journal title
    Topology and its Applications
  • Record number

    1581034