Critical Ising model with boundary magnetic field: RG interface and effective Hamiltonians

  • Anatoly KonechnyEmail author
Open Access
Regular Article - Theoretical Physics


Critical 2D Ising model with a boundary magnetic field is arguably the simplest QFT that interpolates between two non-trivial fixed points. We use the diagonalising Bogolyubov transformation for this model to investigate two quantities. Firstly we explicitly construct an RG interface operator that is a boundary condition changing operator linking the free boundary condition with the one with a boundary magnetic field. We investigate its properties and in particular show that in the limit of large magnetic field this operator becomes the dimension 1/16 primary field linking the free and fixed boundary conditions. Secondly we use Schrieffer-Wolff method to construct effective Hamiltonians both near the UV and IR fixed points.


Effective Field Theories Renormalization Group Conformal Field Theory Nonperturbative Effects 


Open Access

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Copyright information

© The Author(s) 2019

Authors and Affiliations

  1. 1.Department of MathematicsHeriot-Watt UniversityEdinburghU.K.
  2. 2.Maxwell Institute for Mathematical SciencesEdinburghU.K.

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