Additive categories | Homological algebra

Homotopy category of chain complexes

In homological algebra in mathematics, the homotopy category K(A) of chain complexes in an additive category A is a framework for working with chain homotopies and homotopy equivalences. It lies intermediate between the category of chain complexes Kom(A) of A and the derived category D(A) of A when A is abelian; unlike the former it is a triangulated category, and unlike the latter its formation does not require that A is abelian. Philosophically, while D(A) turns into isomorphisms any maps of complexes that are quasi-isomorphisms in Kom(A), K(A) does so only for those that are quasi-isomorphisms for a "good reason", namely actually having an inverse up to homotopy equivalence. Thus, K(A) is more understandable than D(A). (Wikipedia).

Homotopy category of chain complexes
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From playlist Algebraic Topology

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From playlist Algebraic Topology

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From playlist Introduction to Homotopy Theory

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From playlist Introduction to Homotopy Theory

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From playlist Introduction to Homotopy Theory

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From playlist Mathematics

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From playlist Abstract algebra

Related pages

Topological space | Mapping cone (homological algebra) | Abelian category | Chain complex | Additive category | Derived category | Mathematics | Differential graded category | Triangulated category | Homological algebra | Quasi-isomorphism | Quotient