Category:T1/2 Spaces

This category contains results about $T_{\frac 1 2}$ spaces.

Let $T = \struct {S, \tau}$ be a topological space.

Then $T$ is a $T_{\frac 1 2}$ space if and only if:

$\forall A \subseteq S: A'$ is closed

where $A'$ denotes the derivative of $A$.