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sections and retractions
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(Definition)
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Let $f: A\rightarrow B$ is a morphism of a category.
- If there exists morphism $g: B\rightarrow A$ such that $g\circ f=1_A$ then $f$ is called retractable and $g$ is called retraction of $f$
- If there exists morphism $g: B\rightarrow A$ such that $f\circ g=1_B$ then $f$ is called sectionable and $g$ is called section of $f$
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"sections and retractions" is owned by porton.
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(view preamble | get metadata)
See Also: types of morphisms
| Also defines: |
retraction, section, retractable, sectionable |
| Keywords: |
morphism, category theory |
This object's parent.
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Cross-references: category, morphism
There are 11 references to this entry.
This is version 1 of sections and retractions, born on 2009-01-06.
Object id is 11471, canonical name is SectionsAndRetractions.
Accessed 488 times total.
Classification:
| AMS MSC: | 18A05 (Category theory; homological algebra :: General theory of categories and functors :: Definitions, generalizations) |
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Pending Errata and Addenda
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