English
Related papers

Related papers: Control the model sign problem via path optimizati…

200 papers

To tackle the sign problem in the simulations of systems having indefinite or complex-valued measures, we propose a new approach which yields statistical errors smaller than the crude Monte Carlo using absolute values of the original…

High Energy Physics - Lattice · Physics 2008-11-26 T D Kieu , C J Griffin

We consider a class of finite time horizon nonlinear stochastic optimal control problem, where the control acts additively on the dynamics and the control cost is quadratic. This framework is flexible and has found applications in many…

Optimization and Control · Mathematics 2023-04-26 Ajay Jasra , Jeremy Heng , Yaxian Xu , Adrian N. Bishop

We propose new approach to numerical study of quantum spin systems. Our method is based on a fact that one can use any set of states for the path integral as long as it is complete. We apply our method to one-dimensional quantum spin system…

Condensed Matter · Physics 2009-10-22 Tomo Munehisa , Yasuko Munehisa

The canonical approach, which was developed for solving the sign problem, may suffer from a new type of sign problem. In the canonical approach, the grand partition function is written as a fugacity expansion: $Z_G(\mu,T) = \sum_n Z_C(n,T)…

High Energy Physics - Lattice · Physics 2017-05-09 V. A. Goy , V. Bornyakov , D. Boyda , A. Molochkov , A. Nakamura , A. Nikolaev , V. Zakharov

As an intrinsically unbiased method, the quantum Monte Carlo (QMC) method is of unique importance in simulating interacting quantum systems. Although the QMC method often suffers from the notorious sign problem, the sign problem of quantum…

Strongly Correlated Electrons · Physics 2023-08-03 Zhou-Quan Wan , Shi-Xin Zhang , Hong Yao

Accurate thermodynamic simulations of correlated fermions using path integral Monte Carlo (PIMC) methods are of paramount importance for many applications such as the description of ultracold atoms, electrons in quantum dots, and warm-dense…

Computational Physics · Physics 2021-02-03 Tobias Dornheim , Michele Invernizzi , Jan Vorberger , Barak Hirshberg

We present a real-time quantum Monte Carlo algorithm that simulates the dynamics of open quantum systems by stochastically compressing and evolving the density matrix under both Markovian and non-Markovian master equations. Our algorithm…

Quantum Physics · Physics 2025-09-11 Tong Shen , Daniel A. Lidar

Recently, cluster methods have been used to solve a variety of sign problems including those that arise in the presence of fermions. In all cases an analytic partial re-summation over a class of configurations in the path integral was…

High Energy Physics - Lattice · Physics 2009-10-31 Shailesh Chandrasekharan

We investigate the efficiency of a gauge invariant input to a neural network for the path optimization method. While the path optimization with a completely gauge-fixed link-variable input has successfully tamed the sign problem in a simple…

High Energy Physics - Lattice · Physics 2022-02-16 Yusuke Namekawa , Kouji Kashiwa , Akira Ohnishi , Hayato Takase

We address the possibility of performing numerical Monte Carlo simulations for the thermodynamics of quantum dissipative systems. Dissipation is considered within the Caldeira-Leggett formulation, which describes the system in the…

Statistical Mechanics · Physics 2007-05-23 Luca Capriotti , Alessandro Cuccoli , Andrea Fubini , Valerio Tognetti , Ruggero Vaia

The great majority of algorithms employed in the study of lattice field theory are based on Monte Carlo's importance sampling method, i.e. on probability interpretation of the Boltzmann weight. Unfortunately in many theories of interest one…

High Energy Physics - Lattice · Physics 2016-06-03 Lorenzo Bongiovanni

A simple and efficient method for quantum Monte Carlo simulation is presented, based on discretization of the action in the path integral, and a Gaussian averaging of the potential, which works well e.g. with the Coulomb potential.

Computational Physics · Physics 2007-05-23 Jan Myrheim

The negative sign problem in quantum Monte Carlo (QMC) simulations of cluster impurity problems is the major bottleneck in cluster dynamical mean field calculations. In this paper we systematically investigate the dependence of the sign…

Strongly Correlated Electrons · Physics 2015-11-18 Hiroshi Shinaoka , Yusuke Nomura , Silke Biermann , Matthias Troyer , Philipp Werner

First of all, this paper presents some improvements of DSMC method in the form of new schemes and approaches, that, for a wide class of problems, increase performance and reduce the demands on computer resources. The most important…

Fluid Dynamics · Physics 2012-01-16 Roman V. Maltsev

Simulations of QCD suffer from severe critical slowing down towards the continuum limit. This problem is known to be prominent in the topological charge, however, all observables are affected to various degree by these slow modes in the…

High Energy Physics - Lattice · Physics 2011-07-15 Stefan Schaefer , Francesco Virotta

A method is presented to tackle the sign problem in the simulations of systems having indefinite or complex-valued measures. In general, this new approach is shown to yield statistical errors smaller than the crude Monte Carlo using…

High Energy Physics - Lattice · Physics 2008-11-26 T D Kieu , C J Griffin

The wave-function Monte-Carlo method, also referred to as the use of "quantum-jump trajectories", allows efficient simulation of open systems by independently tracking the evolution of many pure-state "trajectories". This method is ideally…

Quantum Physics · Physics 2018-08-22 Michael H. Goerz , Kurt Jacobs

This is a review of recent developments in Monte Carlo methods in the field of ultra cold gases. For bosonic atoms in an optical lattice we discuss path integral Monte Carlo simulations with worm updates and show the excellent agreement…

Quantum Gases · Physics 2015-03-20 Lode Pollet

The numerically exact path integral Monte Carlo approach for the real-time evolution of dissipative quantum systems (PIMC), particularly suited for systems with discrete configuration space (tight-binding systems), is extended to treat…

Statistical Mechanics · Physics 2009-11-11 Lothar Muehlbacher , Charlotte Escher , Joachim Ankerhold

We discuss the sign problem arising in Monte Carlo simulations of frustrated quantum spin systems. We show that for a class of ``semi-frustrated'' systems (Heisenberg models with ferromagnetic couplings $J_z(r) < 0$ along the $z$-axis and…

Strongly Correlated Electrons · Physics 2009-10-31 Patrik Henelius , Anders W. Sandvik