Quasicomponents of Integer Reciprocal Space with Zero are Single Points

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Theorem

Let $A \subseteq \R$ be the set of all points on $\R$ defined as:

$A := \set 0 \cup \set {\dfrac 1 n : n \in \Z_{>0} }$

Let $\struct {A, \tau_d}$ be the integer reciprocal space with zero under the usual (Euclidean) topology.


Then the quasicomponents of $A$ are singletons.


Proof

From Integer Reciprocal Space with Zero is Totally Separated, $A$ is totally separated.

The result follows from Totally Separated iff Quasicomponents are Singletons.

$\blacksquare$


Sources