Journal of High Energy Physics (Oct 2019)

Harmonic analysis and mean field theory

  • Denis Karateev,
  • Petr Kravchuk,
  • David Simmons-Duffin

DOI
https://doi.org/10.1007/JHEP10(2019)217
Journal volume & issue
Vol. 2019, no. 10
pp. 1 – 83

Abstract

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Abstract We review some aspects of harmonic analysis for the Euclidean conformal group, including conformally-invariant pairings, the Plancherel measure, and the shadow transform. We introduce two efficient methods for computing these quantities: one based on weight-shifting operators, and another based on Fourier space. As an application, we give a general formula for OPE coefficients in Mean Field Theory (MFT) for arbitrary spinning operators. We apply this formula to several examples, including MFT for fermions and “seed” operators in 4d, and MFT for currents and stress-tensors in 3d.

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