Title:
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The category of compactifications and its coreflections (English) |
Author:
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Hager, Anthony W. |
Author:
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Wynne, Brian |
Language:
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English |
Journal:
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Commentationes Mathematicae Universitatis Carolinae |
ISSN:
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0010-2628 (print) |
ISSN:
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1213-7243 (online) |
Volume:
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63 |
Issue:
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3 |
Year:
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2022 |
Pages:
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365-378 |
Summary lang:
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English |
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Category:
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math |
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Summary:
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We define ``the category of compactifications'', which is denoted {\bf{CM}}, and consider its family of coreflections, denoted {\bf{corCM}}. We show that {\bf{corCM}} is a complete lattice with bottom the identity and top an interpretation of the Čech--Stone $\beta$. A $c \in${\bf{corCM}} implies the assignment to each locally compact, noncompact $Y$ a compactification minimum for membership in the ``object-range'' of $c$. We describe the minimum proper compactifications of locally compact, noncompact spaces, show that these generate the atoms in {\bf{corCM}} (thus {\bf{corCM}} is not a set), show that any $c \in${\bf{corCM}} not the identity is above an atom, and that $\beta$ is not the supremum of atoms. (English) |
Keyword:
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compactification |
Keyword:
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coreflection |
Keyword:
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atom in a lattice |
MSC:
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06B23 |
MSC:
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18A40 |
MSC:
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54B30 |
MSC:
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54C10 |
MSC:
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54D35 |
idZBL:
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Zbl 07655806 |
idMR:
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MR4542795 |
DOI:
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10.14712/1213-7243.2022.024 |
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Date available:
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2023-02-01T12:11:11Z |
Last updated:
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2024-10-04 |
Stable URL:
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http://hdl.handle.net/10338.dmlcz/151482 |
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Reference:
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Reference:
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Reference:
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Reference:
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Reference:
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