Reversible filters

Alan Dow; Rodrigo Hernández-Gutiérrez

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arXiv · 1601.04081

Reversible filters

Alan Dow·Rodrigo Hernández-Gutiérrez

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Abstract

A space is reversible if every continuous bijection of the space onto itself is a homeomorphism. In this paper we study the question of which countable spaces with a unique non-isolated point are reversible. By Stone duality, these spaces correspond to closed subsets in the Čech-Stone compactification of the natural numbers $βω$. From this, the following natural problem arises: given a space $X$ that is embeddable in $βω$, is it possible to embed $X$ in such a way that the associated filter of neighborhoods defines a reversible (or non-reversible) space? We give the solution to this problem in some cases. It is specially interesting whether the image of the required embedding is a weak $P$-set.

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BibTeX RIS

Alan Dow, Rodrigo Hernández-Gutiérrez. 2016-03-03. Reversible filters. https://arxiv.org/abs/1601.04081

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