This group gathers theorems from algebraic topology, which studies spaces by attaching algebraic invariants such as fundamental groups, homotopy groups, homology, and cohomology. It covers the Hairy Ball theorem on vector fields on spheres, the Hurewicz, Whitehead, and Freudenthal suspension theorems of homotopy theory, Brown representability, the Kunneth and universal coefficient theorems that relate homology with different coefficients or products, Poincare duality for manifolds, and the Leray-Hirsch theorem on the cohomology of fiber bundles.
All Algebraic Topology
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De Rham theorem (Wikipedia)
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In mathematics, more specifically in differential geometry, the de Rham theorem says that the ring homomorphism from the de Rham cohomology to the singular cohomology given by integration is an
View the Source Borsuk-Ulam Theorem (Wikipedia)
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In topology, the Borsuk-Ulam theorem states that every continuous map from the sphere to the plane maps some pair of antipodal points to the same point.
View the Source Mayer-Vietoris Theorem (Wikipedia)
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In algebraic topology and homology theory, the Mayer-Vietoris sequence is an algebraic tool to help compute algebraic invariants of topological spaces.
View the Source Kuiper's theorem, Wikipedia
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In mathematics, Kuiper's theorem (after Nicolaas Kuiper) is a result on the topology of operators on an infinite-dimensional, complex Hilbert space H.
View the Source Hairy Ball Theorem (Wikipedia)
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The hairy ball theorem of algebraic topology (formally, the Sphere Vector Field Theory, sometimes called the hedgehog theorem) states that there is no non-vanishing continuous tangent vector field on even-dimensional n-spheres.
View the Source Hurewicz theorem, Wikipedia
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In mathematics, the Hurewicz theorem is a basic result of algebraic topology, connecting homotopy theory with homology theory via a map known as the Hurewicz homomorphism.
View the Source Whitehead Theorem (Wikipedia)
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In homotopy theory (a branch of mathematics), the Whitehead theorem states that if a continuous mapping f between CW complexes X and Y induces isomorphisms on all homotopy groups, then f is a homotopy equivalence.
View the Source Freudenthal suspension theorem, Wikipedia
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In mathematics, and specifically in the field of homotopy theory, the Freudenthal suspension theorem is the fundamental result leading to the concept of stabilization of homotopy groups and ultimately to stable homotopy theory.
View the Source Brown's representability theorem (Wikipedia)
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In mathematics, Brown's representability theorem in homotopy theory gives necessary and sufficient conditions for a contravariant functor F on the homotopy category Hotc of pointed connected CW complexes, to the category of sets Set, to be a representable functor.
View the Source Leray-Hirsch theorem (Wikipedia)
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In mathematics, the Leray-Hirsch theorem is a basic result on the algebraic topology of fiber bundles.
View the Source Kunneth theorem (Wikipedia)
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In mathematics, especially in homological algebra and algebraic topology, a Künneth theorem, also called a Künneth formula, is a statement relating the homology of two objects to the homology of their product.
View the Source Universal coefficient theorem (Wikipedia)
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In algebraic topology, universal coefficient theorems (UCT) establish relationships between homology groups (or cohomology groups) with different coefficients.
View the Source Poincare Duality Theorem (Wikipedia)
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In mathematics, the Poincaré duality theorem, named after Henri Poincaré, is a basic result on the structure of the homology and cohomology groups of manifolds.
View the Source Seifert-Van Kampen theorem (Wikipedia)
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In mathematics, the Seifert-Van Kampen theorem of algebraic topology (named after Herbert Seifert and Egbert van Kampen), sometimes just called Van Kampen's theorem, expresses the structure of the fundamental group of a topological space X {\displaystyle X} in terms of the fundamental groups of two open, path-connected subspaces that cover X {\displaystyle X} .
View the Source Eilenberg Zilber theorem (Wikipedia)
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specifically in algebraic topology, the Eilenberg-Zilber theorem
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