Excitation Spectrum of the Yang-Lee Singularity of the 2D Ising Model

This paper studies the Yang-Lee edge singularity of 2-dimensional(2D) Ising model through a quantum spin chain. In particular, finite-size scaling measurements on the quantum spin chain are used to determine the central charge and low-lying excitation spectrum at the Yang-Lee edge singularity of the 2D Ising model. The measured values are consistent with predictions for the (A4, A1) minimal conformal field theory.