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Fermion sign problem in imaginary-time projection continuum quantum Monte Carlo with local interaction
Francesco Calcavecchia1, Markus Holzmann2
1LPMMC, 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.
Physical Review. E
|May 14, 2016
Summary
The shadow wave function model reveals the fermion sign problem
Area of Science:
- Computational physics
- Quantum Monte Carlo methods
Background:
- The fermion sign problem hinders quantum Monte Carlo simulations in continuum space.
- Projector quantum Monte Carlo methods are widely used but affected by this issue.
Purpose of the Study:
- To investigate the fermion sign problem using the shadow wave function formalism.
- To analyze the efficiency of imaginary-time projection algorithms.
Main Methods:
- Utilizing the shadow wave function formalism as a computational model.
- Deriving an analytical expression linking system localization and the sign problem magnitude.
Main Results:
- Algorithm efficiency decays exponentially with particle number and propagation time.
- An analytical relationship between system localization and the sign problem is established.
Conclusions:
- The shadow wave function model provides insights into the fermion sign problem's computational complexity.
- Discusses strategies for mitigating the severity of the fermion sign problem in simulations.
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