  We present results of the numerical simulation of the two-dimensional
Thirring model at finite density and temperature. The severe sign problem is
dealt with by deforming the domain of integration into complex field space.
This is the first example where a fermionic sign problem is solved in a quantum
field theory by using the holomorphic gradient flow approach, a generalization
of the Lefschetz thimble method.

High Energy Physics - Lattice