Semidefinite Programs at Finite Fermion Density

Semidefinite programs can be constructed to provide a non-perturbative view of the zero-temperature behavior of quantum systems. This paper examines the properties of these semidefinite programs when applied to lattice-regulated field theories exhibiting fermion sign problems. Specifically on the finite-density Thirring model, there is no indication that the accuracy of semidefinite programs suffers from any difficulty analogous to the sign problem.