Title: Beyond Thimbles: Integration Contours to Solve a Sign Problem
Abstract: For finite-density fermionic field theories, lattice Monte Carlo methods fail because
the Boltzmann weight $e^{-S}$ includes a rapidly oscillating phase. Resolving
the cancellations introduced by these oscillations is too computationally
expensive to be practical: this is the fermion sign problem.
The sign problem can be evaded evaluating the discrete path
integral not over the real plane, but over another integration contour of our
choosing. In this talk I will describe this procedure, as well as different
methods of constructing efficient contours for integration. Results of these
methods, applied to finite-density fermionic theories in 1+1 and 2+1 theories,
are shown.