Field theoretical derivation of Lüscher’s formula and calculation of finite volume form factors

Zoltán Bajnok, János Balog, Márton Lájer, Chao Wu

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5 Citations (Scopus)


We initiate a systematic method to calculate both the finite volume energy levels and form factors from the momentum space finite volume two-point function. By expanding the two point function in the volume we extracted the leading exponential volume correction both to the energy of a moving particle state and to the simplest non-diagonal form factor. The form factor corrections are given in terms of a regularized infinite volume 3-particle form factor and terms related to the Lüsher correction of the momentum quantization. We tested these results against second order Lagrangian and Hamiltonian perturbation theory in the sinh-Gordon theory and we obtained perfect agreement.

Original languageEnglish
Article number174
JournalJournal of High Energy Physics
Issue number7
Publication statusPublished - Jul 1 2018



  • Field Theories in Lower Dimensions
  • Integrable Field Theories
  • Nonperturbative Effects

ASJC Scopus subject areas

  • Nuclear and High Energy Physics

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