Definition:Ordinal Space/Open
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Definition
Let $\Gamma$ be a limit ordinal.
The open ordinal space on $\Gamma$ is the set $\hointr 0 \Gamma$ of all ordinal numbers (strictly) less than $\Gamma$, together with the order topology.
Particular special cases of an open ordinal space are as follows:
Open Ordinal Space: $\Gamma < \Omega$
Let $\Omega$ denote the first uncountable ordinal.
The countable open ordinal space on $\Gamma$ is a particular case of an open ordinal space $\hointr 0 \Gamma$ where $\Gamma < \Omega$.
Open Ordinal Space: $\Gamma = \Omega$
Let $\Omega$ denote the first uncountable ordinal.
The uncountable open ordinal space on $\Omega$ is the particular case of an open ordinal space $\hointr 0 \Gamma$ where $\Gamma = \Omega$.
Also see
- Results about ordinal spaces can be found here.
Sources
- 1978: Lynn Arthur Steen and J. Arthur Seebach, Jr.: Counterexamples in Topology (2nd ed.) ... (previous) ... (next): Part $\text {II}$: Counterexamples: $40, \ 42$. Open Ordinal Space