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We formulate a quantum Monte Carlo (QMC) method for calculating the ground state of many-boson systems. The method is based on a field-theoretical approach, and is closely related to existing fermion auxiliary-field QMC methods which are…

Computational Physics · Physics 2009-11-10 Wirawan Purwanto , Shiwei Zhang

The recently developed auxiliary field diffusion Monte Carlo method is applied to compute the equation of state and the compressibility of neutron matter. By combining diffusion Monte Carlo for the spatial degrees of freedom and auxiliary…

Nuclear Theory · Physics 2009-11-10 A. Sarsa , S. Fantoni , K. E. Schmidt , F. Pederiva

A continuous-time path integral Quantum Monte Carlo method using the directed-loop algorithm is developed to simulate the Anderson single-impurity model in the occupation number basis. Although the method suffers from a sign problem at low…

Strongly Correlated Electrons · Physics 2009-11-10 Jaebeom Yoo , Shailesh Chandrasekharan , Harold U. Baranger

Ab-initio Monte Carlo simulations of strongly-interacting fermionic systems are plagued by the fermion sign problem, making the non-perturbative study of many interesting regimes of dense quantum matter, or of theories of odd numbers of…

High Energy Physics - Lattice · Physics 2024-03-05 Debasish Banerjee , Emilie Huffman

We review a recently proposed approach to the problem of alternating signs for fermionic many body Monte Carlo simulations in finite temperature simulations. We derive an estimate for fermion wandering lengths and introduce the notion of…

High Energy Physics - Lattice · Physics 2009-11-07 Dean Lee

We develop a Monte Carlo scheme for sampling series of Feynman diagrams for the proper self-energy which are self-consistently expressed in terms of renormalized particle propagators. This approach is used to solve the problem of a single…

Strongly Correlated Electrons · Physics 2008-01-08 Nikolay Prokof'ev , Boris Svistunov

We explore correlated electron states in harmonically confined few-electron quantum dots in an external magnetic field by the path-integral Monte Carlo method for a wide range of the field and the Coulomb interaction strength. Using the…

Strongly Correlated Electrons · Physics 2020-01-07 Csaba Tőke , Tamás Haidekker Galambos

We present a new Monte Carlo algorithm for simulating quantum spin systems which is able to suppress the negative sign problem. This algorithm has only a linear complexity in the lattice size used for the simulation. A general description…

High Energy Physics - Lattice · Physics 2007-05-23 A. Galli

The fermion sign problem constitutes one of the most fundamental obstacles in quantum many-body theory. Recently, it has been suggested to circumvent the sign problem by carrying out path integral simulations with a fictitious quantum…

Numerically exact continuous-time Quantum Monte Carlo algorithm for finite fermionic systems with non-local interactions is proposed. The scheme is particularly applicable for general multi-band time-dependent correlations since it does not…

Strongly Correlated Electrons · Physics 2009-11-10 A. N. Rubtsov , A. I. Lichtenstein

We consider the one-dimensional quantum-statistical problem of interacting spin-less particles in an infinite deep potential valley and on a ring. Several limits for the applicability of the Quantum Monte Carlo (QMC) methods were revealed…

Statistical Mechanics · Physics 2007-05-23 Z. Neda , Z. Dezso

Monte Carlo studies involving real time dynamics are severely restricted by the sign problem that emerges from highly oscillatory phase of the path integral. In this letter, we present a new method to compute real time quantities on the…

High Energy Physics - Lattice · Physics 2016-08-24 Andrei Alexandru , Gokce Basar , Paulo F. Bedaque , Sohan Vartak , Neill C. Warrington

The conventional second-order Path Integral Monte Carlo method is plagued with the sign problem in solving many-fermion systems. This is due to the large number of anti-symmetric free fermion propagators that are needed to extract the…

Computational Physics · Physics 2015-06-23 Siu A. Chin

High-energy physics simulations traditionally rely on classical Monte Carlo methods to model complex particle interactions, often incurring significant computational costs. In this paper, we introduce a novel quantum-enhanced simulation…

Quantum Physics · Physics 2025-02-28 Euimin Lee , Sangmin Lee , Shiho Kim

We revisit the infinite variance problem in fermionic Monte Carlo simulations, which is widely encountered in areas ranging from condensed matter to nuclear and high-energy physics. The different algorithms, which we broadly refer to as…

Strongly Correlated Electrons · Physics 2025-12-12 Zhou-Quan Wan , Shiwei Zhang

In low-temperature high-density plasmas quantum effects of the electrons are becoming increasingly important. This requires the development of new theoretical and computational tools. Quantum Monte Carlo methods are among the most…

Statistical Mechanics · Physics 2014-08-12 T. Schoof , S. Groth , M. Bonitz

We present a universal quantum Monte Carlo algorithm for simulating arbitrary high-spin (spin greater than 1/2) Hamiltonians, based on the recently developed permutation matrix representation (PMR) framework. Our approach extends a…

Computational Physics · Physics 2026-01-27 Arman Babakhani , Lev Barash , Itay Hen

Irreversible and rejection-free Monte Carlo methods, recently developed in Physics under the name Event-Chain and known in Statistics as Piecewise Deterministic Monte Carlo (PDMC), have proven to produce clear acceleration over standard…

Computation · Statistics 2020-04-28 Manon Michel , Alain Durmus , Stéphane Sénécal

The fermion bag approach is a new method to tackle fermion sign problems in lattice field theories. Using this approach it is possible to solve a class of sign problems that seem unsolvable by traditional methods. The new solutions emerge…

High Energy Physics - Lattice · Physics 2013-04-18 Shailesh Chandrasekharan

We present an extension of constrained-path auxiliary-field quantum Monte Carlo (CP-AFQMC) for the treatment of correlated electronic systems coupled to phonons. The algorithm follows the standard CP-AFQMC approach for description of the…

Strongly Correlated Electrons · Physics 2021-03-24 Joonho Lee , Shiwei Zhang , David R. Reichman