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Related papers: Screening of a point charge: a fixed-node diffusio…

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Employing a classical density-functional description of liquid environments, we introduce a rigorous method for the diffusion quantum Monte Carlo calculation of free energies and thermodynamic averages of solvated systems that requires…

Monte Carlo approaches to radiation transport have several attractive properties such as simplicity of implementation, high accuracy, and good parallel scaling. Moreover, Monte Carlo methods can handle complicated geometries and are…

Solar and Stellar Astrophysics · Physics 2015-06-04 Ernazar Abdikamalov , Adam Burrows , Christian D. Ott , Frank Löffler , Evan O'Connor , Joshua C. Dolence , Erik Schnetter

We consider the scattering of neutrons and photons on solid volume rectangular targets. It is common to treat this problem using the Maxwell Boltzmann Transport Equation and to use underlying symmetries to simplify the calculation. For…

Computational Physics · Physics 2017-12-27 Eric V. Steinfelds , Keith Andrew

The goal of this effort is to establish the conditions and limits under which the Huygens-Fresnel principle accurately describes diffraction in the Monte Carlo ray-trace environment. This goal is achieved by systematic intercomparison of…

Optics · Physics 2018-05-23 J. R. Mahan , N. Q. Vinh , V. X. Ho , N. B. Munir

The two-dimensional Hubbard model is studied using the variational quantum Monte Carlo technique with Gutzwiller-type variational wave functions. In addition to the simple one-site correlated Gutzwiller wave function, we use a form with…

Strongly Correlated Electrons · Physics 2007-05-23 A. Harju

We report diffusion quantum Monte Carlo calculations of three-dimensional Wigner crystals in the density range r_s=100-150. We have tested different types of orbital for use in the approximate wave functions but none improve upon the simple…

Strongly Correlated Electrons · Physics 2008-01-03 N. D. Drummond , Z. Radnai , J. R. Trail , M. D. Towler , R. J. Needs

Fixed-node Green's function Monte Carlo calculations have been performed for very large 16x6 2D Hubbard lattices, large interaction strengths U=10,20, and 40, and many (15-20) densities between empty and half filling. The nodes were fixed…

Strongly Correlated Electrons · Physics 2009-10-31 A. C. Cosentini , M. Capone , L. Guidoni , G. B. Bachelet

Diffusion Monte Carlo (DMC) is an exact technique to project out the ground state (GS) of a Hamiltonian. Since the GS is always bosonic, in fermionic systems the projection needs to be carried out while imposing anti-symmetric constraints,…

Computational Physics · Physics 2025-01-08 Kousuke Nakano , Sandro Sorella , Dario Alfè , Andrea Zen

We study, through the diffusion Monte Carlo method, a spin one-half fermion fluid, in the three dimensional Euclidean space, at zero temperature. The point particles, immersed in a uniform "neutralizing" background, interact with a…

Strongly Correlated Electrons · Physics 2013-07-11 Riccardo Fantoni

This paper is concerned with differentiable resampling in the context of sequential Monte Carlo (e.g., particle filtering). Drawing on reparametrisation, we propose a new resampling method that is informative and instantly differentiable,…

Machine Learning · Statistics 2026-05-29 Jennifer Rosina Andersson , Zheng Zhao

In this article, we report a fully ab initio variational Monte Carlo study of the linear, and periodic chain of Hydrogen atoms, a prototype system providing the simplest example of strong electronic correlation in low dimensions. In…

Strongly Correlated Electrons · Physics 2015-05-30 Lorenzo Stella , Claudio Attaccalite , Sandro Sorella , Angel Rubio

We review the basic outline of the highly successful diffusion Monte Carlo technique commonly used in contexts ranging from electronic structure calculations to rare event simulation and data assimilation, and propose a new class of…

Numerical Analysis · Mathematics 2017-10-10 Lek-Heng Lim , Jonathan Weare

The aim of this paper is to study the recovery of a spatially dependent potential in a (sub)diffusion equation from overposed final time data. We construct a monotone operator one of whose fixed points is the unknown potential. The…

Numerical Analysis · Mathematics 2022-01-06 Zhengqi Zhang , Zhidong Zhang , Zhi Zhou

Continuum Monte-Carlo simulations at constant pressure are performed on short chain molecules at surfaces. The rodlike chains, consisting of seven effective monomers, are attached at one end to a flat twodimensional substrate. It is found…

Condensed Matter · Physics 2007-05-23 R. Hilfer , F. M. Haas

The doped Fullerides can be well described by a Hubbard model, which comprises the partly filled, threefold-degenerate t_1u orbital and the on-site Coulomb interaction U. The orbital degeneracy is known to shift the critical ratio U_c/W for…

Strongly Correlated Electrons · Physics 2007-05-23 Erik Koch , Olle Gunnarsson , Richard M. Martin

The principle and the efficiency of the Monte Carlo transfer-matrix algorithm are discussed. Enhancements of this algorithm are illustrated by applications to several phase transitions in lattice spin models. We demonstrate how the…

Condensed Matter · Physics 2009-10-28 M. P. Nightingale , H. W. J. Bloete

We discuss the efficiency of Monte Carlo methods in solving continuum radiative transfer problems. The sampling of the radiation field and convergence of dust temperature calculations in the case of optically thick clouds are both studied.…

Astrophysics · Physics 2009-11-10 M. Juvela

Monte Carlo simulations are widely used in many areas including particle accelerators. In this lecture, after a short introduction and reviewing of some statistical backgrounds, we will discuss methods such as direct inversion, rejection…

Computational Physics · Physics 2020-06-19 Ji Qiang

A generalized version of the fidelity susceptibility of single-band and multi-orbital Hubbard models is systematically studied using single-site dynamical mean-field theory in combination with a hybridization expansion continuous-time…

Strongly Correlated Electrons · Physics 2016-12-08 Li Huang , Yilin Wang , Lei Wang , Philipp Werner

We present a highly efficient proximal Markov chain Monte Carlo methodology to perform Bayesian computation in imaging problems. Similarly to previous proximal Monte Carlo approaches, the proposed method is derived from an approximation of…

Computation · Statistics 2020-03-20 Luis Vargas , Marcelo Pereyra , Konstantinos C. Zygalakis