T_{DD}

Last-modified: 2013-04-19 (金) 13:00:32

Definition

  • A topological space (X,τ) is said to be T_{DD} if X is T_D and for all imgtex.fcgi?%5bres=100%5d%7b%5c%5b%20x%2cy%5cin%20X%2c%5c%20x%5cneq%20y%2c%5c%20%5c%7bx%5c%7d'%5ccap%5c%7by%5c%7d'=%5cemptyset%20%5c%5d%7d%25.png (where {x}' is the derived set of {x}).

Property

  • T_{DD} ⇒　T_YS?

Reference

  • Aull, Charles E.; Thron, W.J.,Separation axioms between T0 and T1., (English) [J] Nederl. Akad. Wet., Proc., Ser. A 65, 26-37 (1962).