• Thumbnail for Pontryagin duality
    In mathematics, Pontryagin duality is a duality between locally compact abelian groups that allows generalizing Fourier transform to all such groups, which...
    39 KB (5,806 words) - 03:42, 8 May 2024
  • Thumbnail for Lev Pontryagin
    Lev Pontryagin (redirect from Pontrjagin)
    Pontryagin (Russian: Лев Семёнович Понтрягин, also written Pontriagin or Pontrjagin, first name sometimes anglicized as Leon) (3 September 1908 – 3 May 1988)...
    12 KB (1,032 words) - 00:35, 30 April 2024
  • Thumbnail for Representation theory
    its representation on the space of L2 functions on the unitary dual. Pontrjagin duality and the Peter–Weyl theorem achieve this for abelian and compact...
    55 KB (7,184 words) - 17:41, 8 July 2024
  • group G = Zqω (the countable direct sum) is discrete. Although the Pontrjagin dual Γ is also Zqω, the topology of Γ is compact. One can see that Γ is...
    45 KB (6,916 words) - 19:55, 12 May 2024
  • Akbarov 2009, p. 468. Akbarov 2003, p. 272. Smith, M.F. (1952). "The Pontrjagin duality theorem in linear spaces". Annals of Mathematics. 56 (2): 248–253...
    5 KB (711 words) - 21:26, 7 March 2023
  • abelian group K, equipped with a Haar measure. Such a group has a Pontrjagin dual K ^ {\displaystyle {\hat {K}}} , consisting of all continuous U ( 1...
    32 KB (5,894 words) - 17:23, 16 April 2024
  • unique number such that the group T, equipped with its Haar measure, is Pontrjagin dual to the lattice of integral multiples of 2π. This is a version of the...
    146 KB (17,429 words) - 22:02, 1 September 2024
  • Chow motives of abelian varieties. In string theory, T-duality (short for target space duality), which relates two quantum field theories or string theories...
    7 KB (896 words) - 16:05, 15 August 2024
  • classic reference for differential topology, treating the link to Poincaré duality, Euler class of Sphere bundles, Thom classes and Thom isomorphism, and...
    13 KB (1,978 words) - 18:32, 31 July 2024
  • Thumbnail for Arf invariant
    {\displaystyle S^{1}} with the Lie group framing. The isomorphism here is via the Pontrjagin-Thom construction. Define μ ( x ) ∈ Z 2 {\displaystyle \mu (x)\in \mathbb...
    19 KB (3,422 words) - 10:37, 10 February 2024