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Published on: February 1, 2020
Noise, sign problems, and statistics
Michael G Endres1, David B Kaplan, Jong-Wan Lee
1Theoretical Research Division, RIKEN Nishina Center, Wako, Saitama, Japan. endres@riken.jp
Physical Review Letters
|December 21, 2011
Summary
Sign problems in many-body simulations create heavy-tailed distributions. A new statistical method effectively extracts ground state energies, overcoming these simulation challenges.
Area of Science:
- Computational Physics
- Quantum Many-Body Systems
Background:
- Sign problems hinder accurate simulations of quantum many-body systems.
- These problems can lead to heavy-tailed correlator distributions, mirroring phenomena in electron transport through disordered materials.
Purpose of the Study:
- To demonstrate the connection between sign problems and heavy-tailed distributions in many-body simulations.
- To propose and validate a novel statistical approach for determining ground state energies in systems affected by sign problems.
Main Methods:
- Analysis of correlator distributions in many-body simulations.
- Development of an alternative statistical method for energy extraction.
- Application of the method to a theoretical toy model and lattice data for unitary fermions.
Main Results:
- Established that sign problems manifest as heavy-tailed correlator distributions.
- Successfully extracted ground state energies using the proposed statistical approach.
- Validated the method's efficacy on both model and experimental lattice data.
Conclusions:
- The proposed statistical method offers a viable solution for extracting ground state energies in the presence of sign problems.
- This work provides a new perspective on understanding and mitigating sign problem artifacts in computational physics.
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