Boundary entropy of integrable perturbed SU (2)k WZNW

  • Dinh-Long VuEmail author
  • Ivan Kostov
  • Didina Serban
Open Access
Regular Article - Theoretical Physics


We apply the recently developped analytical methods for computing the boundary entropy, or the g-function, in integrable theories with non-diagonal scattering. We consider the particular case of the current-perturbed SU (2)k WZNW model with boundary and compute the boundary entropy for a specific boundary condition. The main problem we encounter is that in case of non-diagonal scattering the boundary entropy is infinite. We show that this infinity can be cured by a subtraction. The difference of the boundary entropies in the UV and in the IR limits is finite, and matches the known g-functions for the unperturbed SU (2)k WZNW model for even values of the level.


Bethe Ansatz Boundary Quantum Field Theory Integrable Field Theories 


Open Access

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© The Author(s) 2019

Authors and Affiliations

  1. 1.Institut de Physique ThéoriqueGif-sur-YvetteFrance

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