In mathematics, Pontryagin duality is a duality between locally compact abelian groups that allows generalizing Fourier transform to all such groups, which...

Pontryagin (Russian: Лев Семёнович Понтрягин, also written Pontriagin or Pontrjagin, first name sometimes anglicized as Leon) (3 September 1908 – 3 May 1988)...

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...

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...

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...

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...

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...

Chow motives of abelian varieties. In string theory, T-duality (short for target space duality), which relates two quantum field theories or string theories...

classic reference for differential topology, treating the link to Poincaré duality, Euler class of Sphere bundles, Thom classes and Thom isomorphism, and...

the gauge symmetry is an orthogonal group then this class is the first Pontrjagin class. In 3-dimensional gauge theories with Higgs fields, 't Hooft–Polyakov...