Definition:Minimal Hausdorff Topology

Definition

 * Minimal-Hausdorff-topology.png of $a$ and $-a$]]

Let $\omega$ be the first transfinite ordinal.

Let $\struct {A, \tau_1}$ denote the totally ordered set defined as:
 * $A := \set {1, 2, 3, \ldots, \omega, \ldots, -3, -2, -1}$

with the interval topology $\tau_1$.

Let $\struct {\Z_{>0}, \tau_2}$ denote the (strictly) positive integers with the discrete topology $\tau_2$.

Let $S$ be defined as:
 * $S = A \times \Z_{>0} \cup \set {a, -a}$

where $a$ and $-a$ are new elements of $S$.

Let $\tau$ be the topology defined on $S$ as:


 * the product topology on $\struct {A, \tau_1} \times \struct {\Z_{>0}, \tau_2}$

together with neighborhood bases of $a$ and $-a$ defined as:

$\tau$ is referred to as the minimal Hausdorff topology.

The topological space $T = \struct {S, \tau}$ is referred to as the minimal Hausdorff space.

Also see

 * Minimal Hausdorff Topology is Topology