• the Hopf invariant is a homotopy invariant of certain maps between n-spheres. In 1931 Heinz Hopf used Clifford parallels to construct the Hopf map η...
    8 KB (1,542 words) - 06:38, 26 September 2024
  • Thumbnail for Heinz Hopf
    this time Hopf discovered the Hopf invariant of maps S 3 → S 2 {\displaystyle S^{3}\to S^{2}} and proved that the Hopf fibration has invariant 1. In the...
    11 KB (970 words) - 05:12, 25 July 2024
  • Thumbnail for Hopf fibration
    In differential topology, the Hopf fibration (also known as the Hopf bundle or Hopf map) describes a 3-sphere (a hypersphere in four-dimensional space)...
    36 KB (4,813 words) - 13:13, 9 April 2025
  • M^{4m+2}} (for m ≠ 0 , 1 , 3 {\displaystyle m\neq 0,1,3} ) and the mod 2 Hopf invariant of maps S 4 m + 2 + k → S 2 m + 1 + k {\displaystyle S^{4m+2+k}\to S^{2m+1+k}}...
    17 KB (2,366 words) - 19:50, 30 May 2025
  • The Hopf theorem (named after Heinz Hopf) is a statement in differential topology, saying that the topological degree is the only homotopy invariant of...
    967 bytes (103 words) - 17:44, 10 October 2020
  • H-space (redirect from Hopf space)
    It is clear how to define a homotopy from [f][g] to [g][f]. Adams' Hopf invariant one theorem, named after Frank Adams, states that S0, S1, S3, S7 are...
    6 KB (756 words) - 15:17, 18 March 2025
  • 1958 J. Frank Adams published a further generalization in terms of Hopf invariants on H-spaces which still limits the dimension to 1, 2, 4, or 8. It was...
    27 KB (3,215 words) - 22:17, 5 June 2025
  • Thumbnail for Linking number
    Linking number (category Knot invariants)
    differential point of view Hopf invariant – Homotopy invariant of maps between n-spheres Kissing number – Geometric concept Writhe – Invariant of a knot diagram...
    16 KB (2,527 words) - 08:36, 5 March 2025
  • Thumbnail for Homotopy groups of spheres
    S^{15}\hookrightarrow S^{31}\rightarrow S^{16},} the first non-trivial case of the Hopf invariant one problem, because such a fibration would imply that the failed relation...
    83 KB (8,124 words) - 04:10, 28 March 2025
  • Thumbnail for Frank Adams
    classical case. He used this spectral sequence to attack the celebrated Hopf invariant one problem, which he completely solved in a 1960 paper by making a...
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  • In complex geometry, a Hopf surface is a compact complex surface obtained as a quotient of the complex vector space (with zero deleted) C 2 ∖ { 0 } {\displaystyle...
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  • Thumbnail for Hopf link
    In mathematical knot theory, the Hopf link is the simplest nontrivial link with more than one component. It consists of two circles linked together exactly...
    9 KB (892 words) - 16:20, 15 November 2022
  • In mathematics, the Hopf decomposition, named after Eberhard Hopf, gives a canonical decomposition of a measure space (X, μ) with respect to an invertible...
    14 KB (1,877 words) - 11:36, 10 August 2023
  • Thumbnail for Michael Atiyah
    Princeton in 1955. His other collaborators included; J. Frank Adams (Hopf invariant problem), Jürgen Berndt (projective planes), Roger Bielawski (Berry–Robbins...
    83 KB (8,832 words) - 18:56, 18 May 2025
  • Thumbnail for Knot theory
    distinguished using a knot invariant, a "quantity" which is the same when computed from different descriptions of a knot. Important invariants include knot polynomials...
    49 KB (6,298 words) - 14:21, 14 March 2025
  • to coproducts, counits and antipodes of Hopf algebras. Since the Vassiliev invariants (or finite type invariants) are closely related to chord diagrams...
    8 KB (938 words) - 13:12, 2 December 2023
  • Reshetikhin–Turaev invariants (RT-invariants) are a family of quantum invariants of framed links. Such invariants of framed links also give rise to invariants of 3-manifolds...
    9 KB (1,656 words) - 16:44, 8 May 2025
  • Milnor invariants of length k + 1 are defined if all Milnor invariants of length less than or equal to k vanish. The first (2-fold) Milnor invariant is simply...
    8 KB (1,236 words) - 19:46, 18 December 2023
  • Thumbnail for Link (knot theory)
    nontrivial example of a link with more than one component is called the Hopf link, which consists of two circles (or unknots) linked together once. The...
    8 KB (1,107 words) - 22:47, 20 February 2025
  • H_{n}(X;\mathbb {Z} ).} Fibration Hopf fibration Hopf invariant Knot theory Homotopy class Homotopy groups of spheres Topological invariant Homotopy group with coefficients...
    20 KB (3,432 words) - 14:48, 25 May 2025
  • One way to answer the question is using knot polynomials, which are invariants of the knot. If two diagrams have different polynomials, they represent...
    8 KB (960 words) - 07:36, 15 January 2025
  • Thumbnail for Braid group
    to the Yang–Baxter equation (see § Basic properties); and in monodromy invariants of algebraic geometry. In this introduction let n = 4; the generalization...
    36 KB (4,891 words) - 07:38, 7 June 2025
  • In mathematics, and especially gauge theory, Seiberg–Witten invariants are invariants of compact smooth oriented 4-manifolds introduced by Edward Witten (1994)...
    16 KB (2,630 words) - 23:04, 2 March 2025
  • Thumbnail for Exceptional object
    spheres" by R. Bott and J. Milnor and "On the nonexistence of elements of Hopf invariant one" by J. F. Adams". Bulletin of the American Mathematical Society...
    25 KB (3,088 words) - 15:48, 11 November 2024
  • Steenrod algebra (category Hopf algebras)
    appropriate Adem relations, was the solution by J. Frank Adams of the Hopf invariant one problem. One application of the mod 2 Steenrod algebra that is fairly...
    30 KB (5,577 words) - 03:49, 29 May 2025
  • structure of a Hopf algebra is when considering all H-modules as a category. The additional structure is also used to define invariant elements of an...
    6 KB (1,184 words) - 22:22, 1 June 2025
  • Thumbnail for Knot invariant
    In the mathematical field of knot theory, a knot invariant is a quantity (in a broad sense) defined for each knot which is the same for equivalent knots...
    10 KB (1,278 words) - 16:18, 12 January 2025
  • They were introduced by J. Frank Adams (1960) in his solution to the Hopf invariant problem. Similarly, one can define tertiary cohomology operations from...
    2 KB (281 words) - 06:24, 16 October 2024
  • Topological K-theory has been applied in John Frank Adams’ proof of the “Hopf invariant one” problem via Adams operations. Adams also proved an upper bound...
    9 KB (1,349 words) - 19:33, 7 January 2025
  • In mathematics, the Alexander polynomial is a knot invariant which assigns a polynomial with integer coefficients to each knot type. James Waddell Alexander...
    17 KB (2,622 words) - 22:00, 9 May 2025