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arXiv · 2009.08601

Galvin's Question on non-$\sigma$-Well Ordered Linear Orders

Hossein Lamei Ramandi
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Abstract

Assume $\mathcal{C}$ is the class of all linear orders $L$ such that $L$ is not a countable union of well ordered sets, and every uncountable subset of $L$ contains a copy of $\omega_1$. We show it is consistent that $\mathcal{C}$ has minimal elements. This answers an old question due to Galvin.

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BibTeXRIS

Hossein Lamei Ramandi. 2020-09-18. Galvin's Question on non-$\sigma$-Well Ordered Linear Orders. https://arxiv.org/abs/2009.08601

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