enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Sheaf (mathematics) - Wikipedia

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

    Especially in the context of sheaves on manifolds, sheaf cohomology can often be computed using resolutions by soft sheaves, fine sheaves, and flabby sheaves (also known as flasque sheaves from the French flasque meaning flabby). For example, a partition of unity argument shows that the sheaf of smooth functions on a manifold is soft.

  3. Image functors for sheaves - Wikipedia

    en.wikipedia.org/wiki/Image_functors_for_sheaves

    In mathematics, especially in sheaf theory—a domain applied in areas such as topology, logic and algebraic geometry—there are four image functors for sheaves that belong together in various senses. Given a continuous mapping f: X → Y of topological spaces, and the category Sh(–) of sheaves of abelian groups on a topological space. The ...

  4. Differentiable manifold - Wikipedia

    en.wikipedia.org/wiki/Differentiable_manifold

    Let M be a topological space.A chart (U, φ) on M consists of an open subset U of M, and a homeomorphism φ from U to an open subset of some Euclidean space R n.Somewhat informally, one may refer to a chart φ : U → R n, meaning that the image of φ is an open subset of R n, and that φ is a homeomorphism onto its image; in the usage of some authors, this may instead mean that φ : U → R n ...

  5. Exponential sheaf sequence - Wikipedia

    en.wikipedia.org/wiki/Exponential_sheaf_sequence

    In mathematics, the exponential sheaf sequence is a fundamental short exact sequence of sheaves used in complex geometry. Let M be a complex manifold, and write O M for the sheaf of holomorphic functions on M. Let O M * be the subsheaf consisting of the non-vanishing holomorphic functions. These are both sheaves of abelian groups.

  6. Coherent sheaf - Wikipedia

    en.wikipedia.org/wiki/Coherent_sheaf

    Coherent sheaves can be seen as a generalization of vector bundles. Unlike vector bundles, they form an abelian category, and so they are closed under operations such as taking kernels, images, and cokernels. The quasi-coherent sheaves are a generalization of coherent sheaves and include the locally free sheaves of infinite rank.

  7. Dodge C series - Wikipedia

    en.wikipedia.org/wiki/Dodge_C_Series

    It replaced the Dodge B series of trucks and was eventually supplanted by the Dodge D series, introduced in 1961. Unlike the B series, which were closely related to Dodge's prewar trucks, the C series was a complete redesign. Dodge continued the "pilot house" tradition of high-visibility cabs with a wrap-around windshield introduced in 1955.

  8. Simplicial presheaf - Wikipedia

    en.wikipedia.org/wiki/Simplicial_presheaf

    The category of simplicial presheaves on a site admits many different model structures.. Some of them are obtained by viewing simplicial presheaves as functors The category of such functors is endowed with (at least) three model structures, namely the projective, the Reedy, and the injective model structure.

  9. Sheaf of modules - Wikipedia

    en.wikipedia.org/wiki/Sheaf_of_modules

    In mathematics, a sheaf of O-modules or simply an O-module over a ringed space (X, O) is a sheaf F such that, for any open subset U of X, F(U) is an O(U)-module and the restriction maps F(U) → F(V) are compatible with the restriction maps O(U) → O(V): the restriction of fs is the restriction of f times the restriction of s for any f in O(U) and s in F(U).