COMMENTS ON THE FIELD-THEORETIC FORMULATION OF THE YANG-LEE EDGE SINGULARITY

Fisher has recently shown that the character of the Yang-Lee edge singularity may be obtained from a one-component field theory with pure imaginary phi 3 coupling. The authors point out that phi 4 interactions are not required to stabilise this theory and that, even if they are present, their contribution is likely to be insignificant compared with that from the phi 3 interactions, as the dimension of space is lowered through four.