When.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. Tor functor - Wikipedia

    en.wikipedia.org/wiki/Tor_functor

    Tor functor. In mathematics, the Tor functors are the derived functors of the tensor product of modules over a ring. Along with the Ext functor, Tor is one of the central concepts of homological algebra, in which ideas from algebraic topology are used to construct invariants of algebraic structures.

  4. Analysis Situs (paper) - Wikipedia

    en.wikipedia.org/wiki/Analysis_Situs_(paper)

    "Analysis Situs" is a seminal mathematics paper that Henri Poincaré published in 1895. [1] Poincaré published five supplements to the paper between 1899 and 1904. [2]These papers provided the first systematic treatment of topology and revolutionized the subject by using algebraic structures to distinguish between non-homeomorphic topological spaces, founding the field of algebraic topology. [3]

  5. Étale fundamental group - Wikipedia

    en.wikipedia.org/wiki/Étale_fundamental_group

    In algebraic topology, the fundamental group of a pointed topological space is defined as the group of homotopy classes of loops based at . This definition works well for spaces such as real and complex manifolds, but gives undesirable results for an algebraic variety with the Zariski topology. In the classification of covering spaces, it is ...

  6. Algebraic geometry and analytic geometry - Wikipedia

    en.wikipedia.org/wiki/Algebraic_geometry_and...

    The topology on X an is called the "complex topology" (and is very different from the subspace topology). Suppose φ: X → Y is a morphism of schemes of locally finite type over C. Then there exists a continuous map φ an: X an → Y an such that λ Y ∘ φ an = φ ∘ λ X.

  7. Eilenberg–Steenrod axioms - Wikipedia

    en.wikipedia.org/wiki/Eilenberg–Steenrod_axioms

    In mathematics, specifically in algebraic topology, the Eilenberg–Steenrod axioms are properties that homology theories of topological spaces have in common. The quintessential example of a homology theory satisfying the axioms is singular homology, developed by Samuel Eilenberg and Norman Steenrod. One can define a homology theory as a ...

  8. A¹ homotopy theory - Wikipedia

    en.wikipedia.org/wiki/A¹_homotopy_theory

    A¹ homotopy theory. In algebraic geometry and algebraic topology, branches of mathematics, A1 homotopy theory or motivic homotopy theory is a way to apply the techniques of algebraic topology, specifically homotopy, to algebraic varieties and, more generally, to schemes. The theory is due to Fabien Morel and Vladimir Voevodsky.

  9. Čech cohomology - Wikipedia

    en.wikipedia.org/wiki/Čech_cohomology

    The idea of Čech cohomology is that, for an open cover consisting of sufficiently small open sets, the resulting simplicial complex should be a good combinatorial model for the space X. For such a cover, the Čech cohomology of X is defined to be the simplicial cohomology of the nerve. This idea can be formalized by the notion of a good cover.