title: Fermion sign problem in imaginary-time projection continuum quantum Monte Carlo with local interaction.
abstract: We use the shadow wave function formalism as a convenient model to study the fermion sign problem affecting all projector quantum Monte Carlo methods in continuum space. We demonstrate that the efficiency of imaginary-time projection algorithms decays exponentially with increasing number of particles and/or imaginary-time propagation. Moreover, we derive an analytical expression that connects the localization of the system with the magnitude of the sign problem, illustrating this behavior through numerical results. Finally, we discuss the computational complexity of the fermion sign problem and methods for alleviating its severity.
authors.affiliation: LPMMC, UMR 5493 of CNRS, Université Grenoble Alpes, 38042 Grenoble, France; Institute of Physics, Johannes Gutenberg University, Staudingerweg 7, D-55128 Mainz, Germany; and Graduate School of Excellence Materials Science in Mainz, Staudingerweg 9, D-55128 Mainz, Germany.
authors.forename: Francesco
authors.initials: F
authors.lastname: Calcavecchia
authors.affiliation: LPMMC, UMR 5493 of CNRS, Université Grenoble Alpes, 38042 Grenoble, France and Institut Laue Langevin, BP 156, F-38042 Grenoble Cedex 9, France.
authors.forename: Markus
authors.initials: M
authors.lastname: Holzmann