enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Algebraic topology - Wikipedia

    en.wikipedia.org/wiki/Algebraic_topology

    Algebraic topology is a branch of mathematics that uses tools from abstract algebra to study topological spaces. The basic goal is to find algebraic invariants that classify topological spaces up to homeomorphism, though usually most classify up to homotopy equivalence. Although algebraic topology primarily uses algebra to study topological ...

  3. H-space - Wikipedia

    en.wikipedia.org/wiki/H-space

    As such, the existence of an H-space structure on a given space is only dependent on pointed homotopy type. The multiplicative structure of an H-space adds structure to its homology and cohomology groups. For example, the cohomology ring of a path-connected H-space with finitely generated and free cohomology groups is a Hopf algebra. [9]

  4. Homology (mathematics) - Wikipedia

    en.wikipedia.org/wiki/Homology_(mathematics)

    In mathematics, the term homology, originally introduced in algebraic topology, has three primary, closely-related usages.The most direct usage of the term is to take the homology of a chain complex, resulting in a sequence of abelian groups called homology groups.

  5. Homotopy theory - Wikipedia

    en.wikipedia.org/wiki/Homotopy_theory

    In homotopy theory and algebraic topology, the word "space" denotes a topological space.In order to avoid pathologies, one rarely works with arbitrary spaces; instead, one requires spaces to meet extra constraints, such as being compactly generated weak Hausdorff or a CW complex.

  6. Directed algebraic topology - Wikipedia

    en.wikipedia.org/wiki/Directed_algebraic_topology

    Given two directed paths γ and δ, a directed homotopy from γ to δ is a morphism of directed spaces h whose underlying map U(h) is a homotopy –in the usual sense– between the underlying paths U(γ) and U(δ). In algebraic topology, there is a homotopy from α to β if and only if there is a homotopy from β to α. Due to non ...

  7. Pushforward (homology) - Wikipedia

    en.wikipedia.org/wiki/Pushforward_(homology)

    In algebraic topology, the pushforward of a continuous function : between two topological spaces is a homomorphism: () between the homology groups for . Homology is a functor which converts a topological space X {\displaystyle X} into a sequence of homology groups H n ( X ) {\displaystyle H_{n}\left(X\right)} .

  8. Eilenberg–MacLane space - Wikipedia

    en.wikipedia.org/wiki/Eilenberg–MacLane_space

    In mathematics, specifically algebraic topology, an Eilenberg–MacLane space [note 1] is a topological space with a single nontrivial homotopy group. Let G be a group and n a positive integer . A connected topological space X is called an Eilenberg–MacLane space of type K ( G , n ) {\displaystyle K(G,n)} , if it has n -th homotopy group π n ...

  9. Lefschetz hyperplane theorem - Wikipedia

    en.wikipedia.org/wiki/Lefschetz_hyperplane_theorem

    A result of this kind was first stated by Solomon Lefschetz for homology groups of complex algebraic varieties. Similar results have since been found for homotopy groups, in positive characteristic, and in other homology and cohomology theories. A far-reaching generalization of the hard Lefschetz theorem is given by the decomposition theorem.