left-invertible subcategory

  • 1Monoid — This article is about the mathematical concept. For the alien creatures in the Doctor Who adventure, see The Ark (Doctor Who). Coherence law for monoid unit In abstract algebra, a branch of mathematics, a monoid is an algebraic structure with a… …

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  • 2Category (mathematics) — In mathematics, a category is an algebraic structure that comprises objects that are linked by arrows . A category has two basic properties: the ability to compose the arrows associatively and the existence of an identity arrow for each object. A …

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  • 3Gluing axiom — In mathematics, the gluing axiom is introduced to define what a sheaf F on a topological space X must satisfy, given that it is a presheaf, which is by definition a contravariant functor : F : O ( X ) rarr; C to a category C which initially one… …

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