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arXiv · 2112.11954

When is a category of adherence-determined convergences simple?

Frédéric Mynard·Jerzy Wojciechowski
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Abstract

Abstract. We provide a characterization of classes of filters $\mathbb{D}$ for which the full subcategory $\operatorname{fix}\operatorname{A}_{\mathbb D}$ of $\mathsf{Conv}$ formed by convergences determined by the adherence of filters of the class $\mathbb{D}$ is simple in $\mathsf{Conv}$. Along the way, we also elucidate when two classes of filters result in the same category of adherence-determined convergences. As an application of the main result, we show that the category of hypotopologies is not simple, thus answering a question from [25].

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Frédéric Mynard, Jerzy Wojciechowski. 2021-12-22. When is a category of adherence-determined convergences simple?. https://doi.org/10.1016/j.topol.2022.108319

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