Functional renormalization group approach to dipolar fixed point which is scale-invariant but non-conformal

Abstract

A dipolar fixed point introduced by Aharony and Fisher is a physical example of interacting scale-invariant but non-conformal field theories. We find that the perturbative critical exponents computed in $\epsilon$ expansions violate the conformal bootstrap bound. We formulate the functional renormalization group equations a la Wetterich and Polchinski to study the fixed point. We present some results in three dimensions within (uncontrolled) local potential approximations (with or without perturbative anomalous dimensions).

15 pages