• Thumbnail for Arf invariant
    mathematics, the Arf invariant of a nonsingular quadratic form over a field of characteristic 2 was defined by Turkish mathematician Cahit Arf (1941) when...
    19 KB (3,422 words) - 02:57, 13 May 2025
  • have Arf–Kervaire invariant equal to 0, or half have Arf–Kervaire invariant 0 and the other half have Arf–Kervaire invariant 1. The Kervaire invariant problem...
    17 KB (2,366 words) - 06:20, 10 May 2025
  • Cahit Arf (Turkish: [dʒaːhit aɾf]; 24 October 1910 – 26 December 1997) was a Turkish mathematician. He is known for the Arf invariant of a quadratic form...
    11 KB (991 words) - 11:05, 12 May 2025
  • the mathematical field of knot theory, the Arf invariant of a knot, named after Cahit Arf, is a knot invariant obtained from a quadratic form associated...
    5 KB (739 words) - 21:40, 27 July 2024
  • Thumbnail for Trefoil knot
    requires the construction of a knot invariant that distinguishes the trefoil from the unknot. The simplest such invariant is tricolorability: the trefoil...
    10 KB (1,313 words) - 18:05, 5 May 2025
  • ribosylation factor, a small GTP-binding protein The Arf invariant in mathematics Argon fluoride laser or ArF laser Atomic Resonance Filter or atomic line filter...
    929 bytes (130 words) - 23:04, 19 December 2024
  • {1}}6} . where Arf ⁡ ( M , Σ ) {\displaystyle \operatorname {Arf} (M,\Sigma )} is the Arf invariant of a certain quadratic form on H 1 ( Σ , Z / 2 Z ) {\displaystyle...
    10 KB (1,517 words) - 17:15, 21 December 2023
  • Thumbnail for Seifert surface
    isotopic either topologically or smoothly in the 4-ball. Crosscap number Arf invariant of a knot Murasugi sum Slice genus Seifert, H. (1934). "Über das Geschlecht...
    10 KB (1,358 words) - 07:56, 18 July 2024
  • is an invariant of order two. Modulo two, it is equal to the Arf invariant. Any coefficient of the Kontsevich invariant is a finite type invariant. The...
    5 KB (626 words) - 21:03, 27 July 2024
  • Thumbnail for Unknot
    Unknot (section Invariants)
    a particular knot is the unknot was a major driving force behind knot invariants, since it was thought this approach would possibly give an efficient algorithm...
    5 KB (589 words) - 15:01, 15 August 2024
  • 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
  • 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
  • generalized Jones polynomial, is a 2-variable knot polynomial, i.e. a knot invariant in the form of a polynomial of variables m and l. A central question in...
    5 KB (737 words) - 04:40, 25 November 2024
  • singly even dimension (4k+2), the L-groups detect the Arf invariant (topologically the Kervaire invariant). The symmetric L-groups of the integers are: L 4...
    6 KB (1,062 words) - 19:23, 15 October 2023
  • Thumbnail for Knot polynomial
    In the mathematical field of knot theory, a knot polynomial is a knot invariant in the form of a polynomial whose coefficients encode some of the properties...
    5 KB (416 words) - 23:48, 22 June 2024
  • quaternion groups. The corresponding quadratic form (see below) has Arf invariant 1. The central product of n extraspecial groups of order 8, an even...
    8 KB (1,238 words) - 01:52, 22 June 2023
  • Thumbnail for Figure-eight knot (mathematics)
    Figure-eight knot Common name Figure-eight knot Arf invariant 1 Braid length 4 Braid no. 3 Bridge no. 2 Crosscap no. 2 Crossing no. 4 Genus 1 Hyperbolic...
    9 KB (1,092 words) - 16:00, 16 April 2025
  • Gromov–Witten invariant Arf invariant Hopf invariant Invariant theory Framed knot Chern–Simons theory Algebraic geometry Seifert surface Geometric invariant theory...
    4 KB (347 words) - 01:28, 2 May 2024
  • Jones polynomial (category Knot invariants)
    polynomial discovered by Vaughan Jones in 1984. Specifically, it is an invariant of an oriented knot or link which assigns to each oriented knot or link...
    17 KB (2,352 words) - 23:01, 4 January 2025
  • Thumbnail for Tricolorability
    Tricolorability (category Knot invariants)
    three colors subject to certain rules. Tricolorability is an isotopy invariant, and hence can be used to distinguish between two different (non-isotopic)...
    6 KB (667 words) - 18:42, 25 September 2024
  • Thumbnail for Turkish people
    component of 5G technologies. Mathematician Cahit Arf is known for Hasse–Arf theorem and Arf invariant. Physician Hulusi Behçet discovered Behçet's disease...
    248 KB (25,601 words) - 08:45, 6 May 2025
  • Thumbnail for Slice knot
    {\displaystyle =\Delta (-1)} ) is a square number. The signature is an invariant of concordance classes and the signature of slice knots is zero. Furthermore...
    13 KB (2,017 words) - 23:24, 16 January 2024
  • Thumbnail for Prime knot
    Prime knot (category Knot invariants)
    (42 1) Invariants Alternating Arf invariant Bridge no. 2-bridge Brunnian Chirality Invertible Crosscap no. Crossing no. Finite type invariant Hyperbolic...
    3 KB (280 words) - 16:09, 5 January 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 Perko pair
    by Little in 1900 that the writhe of a reduced diagram of a knot is an invariant (see Tait conjectures), as the two diagrams for the pair have different...
    4 KB (350 words) - 04:29, 16 April 2025
  • Thumbnail for Crossing number (knot theory)
    Crossing number (knot theory) (category Knot invariants)
    smallest number of crossings of any diagram of the knot. It is a knot invariant. By way of example, the unknot has crossing number zero, the trefoil knot...
    6 KB (573 words) - 23:43, 2 April 2024
  • are just called quadratic forms. The Arf invariant of a nonsingular quadratic form over F2 is an F2-valued invariant with important applications in both...
    12 KB (1,784 words) - 05:04, 21 May 2023
  • Thumbnail for Linking number
    Linking number (category Knot invariants)
    In mathematics, the linking number is a numerical invariant that describes the linking of two closed curves in three-dimensional space. Intuitively, the...
    16 KB (2,527 words) - 08:36, 5 March 2025
  • a quadratic form in characteristic 2 is of interest related to the Arf invariant – Irving Kaplansky (1974), Linear Algebra and Geometry, p. 27. The bilinear...
    33 KB (4,569 words) - 21:18, 22 March 2025
  • Thumbnail for Borromean rings
    are used. The number of colorings meeting these conditions is a knot invariant, independent of the diagram chosen for the link. A trivial link with three...
    43 KB (4,472 words) - 11:29, 20 October 2024