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arXiv · 1904.09663

Fehrele's principle in nonstandard topology

Takuma Imamura
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Abstract

In nonstandard analysis, Fehrele's principle is a beautiful criterion for a set to be internal, stating that every galactic halic set is internal. In this note, we use this principle to prove some well-known results in topology, including slight generalisations of the Moore-Osgood theorem and Dini's theorem.

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Takuma Imamura. 2019-04-21. Fehrele's principle in nonstandard topology. https://arxiv.org/abs/1904.09663

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