Abstract
The basic result here is that certain easily described coreflective subcategories S of the category CRFrm of completely regular frames have unique essential completions determined for each L ∈ S by the S-coreflection of the Booleanization of L. Next, this is shown to apply to several familiar subcategories of CRFrm, and concrete descriptions of the essential completions as well as internal characterizations of essential completeness are then given for these cases. Finally, back to the subcategories S in general, the essential completions in any of these are proved to become the epicomplete reflections in the category derived from S by considering only skeletal maps.
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Banaschewski, B., Hager, A.W. Essential Completeness in Categories of Completely Regular Frames. Appl Categor Struct 21, 167–180 (2013). https://doi.org/10.1007/s10485-011-9262-3
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DOI: https://doi.org/10.1007/s10485-011-9262-3
Keywords
- Completely regular frame
- Essential monomorphism
- Essential completion
- Strongly monocoreflective subcategory
- Booleanization of a frame