Form factors of descendant operators: reduction to perturbed M (2, 2s + 1) models

  • Michael LashkevichEmail author
  • Yaroslav Pugai
Open Access
Regular Article - Theoretical Physics


In the framework of the algebraic approach to form factors in two-dimensional integrable models of quantum field theory we consider the reduction of the sine-Gordon model to the Φ13-perturbation of minimal conformal models of the M (2, 2s + 1) series. We find in an algebraic form the condition of compatibility of local operators with the reduction. We propose a construction that make it possible to obtain reduction compatible local operators in terms of screening currents. As an application we obtain exact multiparticle form factors for the compatible with the reduction conserved currents T±2k, Θ±(2k−2), which correspond to the spin ±(2k − 1) integrals of motion, for any positive integer k. Furthermore, we obtain all form factors of the operators T2k T−2l, which generalize the famous \( T\overline{T} \) operator. The construction is analytic in the s parameter and, therefore, makes sense in the sine-Gordon theory.


Integrable Field Theories Exact S-Matrix Quantum Groups 


Open Access

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Copyright information

© The Author(s) 2015

Authors and Affiliations

  1. 1.Landau Institute for Theoretical PhysicsChernogolovkaRussia
  2. 2.Moscow Institute of Physics and TechnologyDolgoprudnyRussia
  3. 3.Kharkevich Institute for Information Transmission ProblemsMoscowRussia

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