Bootstrapping 3D fermions

Abstract

We study the conformal bootstrap for a 4-point function of fermions <psi psi psi psi > in 3D. We first introduce an embedding formalism for 3D spinors and compute the conformal blocks appearing in fermion 4-point functions. Using these results, we find general bounds on the dimensions of operators appearing in the psi x psi OPE, and also on the central charge C (T) . We observe features in our bounds that coincide with scaling dimensions in the Gross-Neveu models at large N. We also speculate that other features could coincide with a fermionic CFT containing no relevant scalar operators.