Effective quasi-Polish categories of overt discrete spaces and compact Hausdorff spaces

Matthew de Brecht

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arXiv · 2608.23648

Effective quasi-Polish categories of overt discrete spaces and compact Hausdorff spaces

Matthew de Brecht

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Abstract

We construct the category of overt discrete quasi-Polish spaces and the category of compact Hausdorff quasi-Polish spaces (and some of their subcategories) as internal categories of the category of effective quasi-Polish spaces and computable maps. To demonstrate that the constructions are natural, we show that Stone duality is computable, in the sense that the dual contravariant functors and the natural transformations demonstrating their adjointness are computable.

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Matthew de Brecht. 2026-08-24. Effective quasi-Polish categories of overt discrete spaces and compact Hausdorff spaces. https://arxiv.org/abs/2608.23648

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