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  • Letter
  • Open Access

Ising model close to d=2

Wenliang Li*

  • School of Physics, Sun Yat-Sen University, Guangzhou 510275, China and Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan

  • *liwliang3@mail.sysu.edu.cn
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Phys. Rev. D 105, L091902 – Published 11 May, 2022

DOI: https://doi.org/10.1103/PhysRevD.105.L091902

Abstract

The d=2 critical Ising model is described by an exactly solvable conformal field theory (CFT). The deformation to d=2+ε is a relatively simple system at strong coupling outside of even dimensions. Using novel numerical and analytical conformal bootstrap methods in Lorentzian signature, we show that the leading corrections to the Ising data are more singular than ε. There must be infinitely many new states due to the d-dependence of conformal symmetry. The linear independence of conformal blocks is central to this bootstrap approach, which can be extended to more rigorous studies of nonpositive systems, such as nonunitary, defect/boundary and thermal CFTs.

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Phys. Rev. D 105, L091902– Published 11 May, 2022
  • Received 17 January 2022
  • Accepted 25 April 2022
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