A conformal truncation framework for infinite-volume dynamics

  • Emanuel Katz
  • Zuhair U. Khandker
  • Matthew T. Walters
Open Access
Regular Article - Theoretical Physics


We present a new framework for studying conformal field theories deformed by one or more relevant operators. The original CFT is described in infinite volume using a basis of states with definite momentum, P , and conformal Casimir, C. The relevant deformation is then considered using lightcone quantization, with the resulting Hamiltonian expressed in terms of this CFT basis. Truncating to states with \( \mathcal{C}\le {\mathcal{C}}_{\max } \), one can numerically find the resulting spectrum, as well as other dynamical quantities, such as spectral densities of operators. This method requires the introduction of an appropriate regulator, which can be chosen to preserve the conformal structure of the basis. We check this framework in three dimensions for various perturbative deformations of a free scalar CFT, and for the case of a free O(N ) CFT deformed by a mass term and a non-perturbative quartic interaction at large-N . In all cases, the truncation scheme correctly reproduces known analytic results. We also discuss a general procedure for generating a basis of Casimir eigenstates for a free CFT in any number of dimensions.


AdS-CFT Correspondence Conformal and W Symmetry Nonperturbative Effects 


Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.


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Copyright information

© The Author(s) 2016

Authors and Affiliations

  • Emanuel Katz
    • 1
  • Zuhair U. Khandker
    • 1
  • Matthew T. Walters
    • 1
  1. 1.Department of PhysicsBoston UniversityBostonU.S.A.

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