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Related papers: Stabilising complex Langevin simulations

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We study lattice QCD at non-vanishing chemical potential using the complex Langevin equation. We compare the results with multi-parameter reweighting both from $\mu=0$ and phase quenched ensembles. We find a good agreement for lattice…

High Energy Physics - Lattice · Physics 2015-12-02 Z. Fodor , S. D. Katz , D. Sexty , C. Török

Following the Killip-Kiselev-Last method, we prove quantum dynamical upper bounds for discrete one-dimensional Schr\"odinger operators with Sturmian potentials. These bounds hold for sufficiently large coupling, almost every rotation…

Mathematical Physics · Physics 2014-12-30 David Damanik

A non-relativistic system such as an ultracold trapped ion may perform a quantum simulation of a Dirac equation dynamics under specific conditions. The resulting Hamiltonian and dynamics are highly controllable, but the coupling between…

Quantum Physics · Physics 2017-02-24 Xue-Ke Song , Fu-Guo Deng , Lucas Lamata , J. G. Muga

QCD thermodynamics is considered using Wilson fermions in the fixed scale approach. The temperature dependence of the renormalized chiral condensate, quark number susceptibility and Polyakov loop is measured at four lattice spacings…

High Energy Physics - Lattice · Physics 2015-06-05 S. Borsanyi , S. Durr , Z. Fodor , C. Hoelbling , S. D. Katz , S. Krieg , D. Nogradi , B. C. Toth , N. Trombitas , K. K. Szabo

Control of linear dynamics with multiplicative noise naturally introduces robustness against dynamical uncertainty. Moreover, many physical systems are subject to multiplicative disturbances. In this work we show how these dynamics can be…

Optimization and Control · Mathematics 2023-12-27 Peter Coppens , Panagiotis Patrinos

We use complex Langevin simulations to study the QCD phase diagram with two light quark flavours. In this study, we use Wilson fermions with an intermediate pion mass of $\sim480\,$MeV. By studying thermodynamic quantities, in particular at…

High Energy Physics - Lattice · Physics 2023-01-11 Felipe Attanasio , Benjamin Jäger , Felix P. G. Ziegler

We describe collective-move Monte Carlo algorithms designed to approximate the overdamped dynamics of self-assembling nanoscale components equipped with strong, short-ranged and anisotropic interactions. Conventional Monte Carlo simulations…

Statistical Mechanics · Physics 2012-04-16 Stephen Whitelam

We put the Density-of-States (DoS) approach to Monte-Carlo (MC) simulations under a stress test by applying it to a physical problem with the worst possible sign problem: the real time evolution of a non-integrable quantum spin chain.…

Statistical Mechanics · Physics 2023-02-27 Pavel Buividovich , Johann Ostmeyer

A discrete quantum spin system is presented in which several modern methods of canonical quantum gravity can be tested with promising results. In particular, features of interacting dynamics are analyzed with an emphasis on homogeneous…

General Relativity and Quantum Cosmology · Physics 2017-04-19 Bekir Baytaş , Martin Bojowald

We explore the region of small sea quark masses below $m_{PS}/m_V=0.5$ in two-flavor QCD using a mean-field improved clover quark action and an RG-improved gauge action at $a \simeq 0.2$ fm on $12^3 \times 24$ and $16^3 \times 24$ lattices.…

A first study of numerical Monte Carlo simulations with two quark doublets, a mass-degenerate one and a mass-split one, interpreted as u, d, s and c quarks, is carried out in the framework of the twisted mass Wilson lattice formulation.…

High Energy Physics - Lattice · Physics 2008-11-26 T. Chiarappa , F. Farchioni , K. Jansen , I. Montvay , E. E. Scholz , L. Scorzato , T. Sudmann , C. Urbach

Close to the chiral limit, many calculations in numerical lattice QCD can potentially be accelerated using low-mode deflation techniques. In this paper it is shown that the recently introduced domain-decomposed deflation subspaces can be…

High Energy Physics - Lattice · Physics 2008-11-26 Martin Lüscher

We introduce a projected complex Langevin (CL) numerical sampling method -- a fictitious Langevin dynamics scheme that uses numerical projection to sample a constrained stationary distribution with highly oscillatory character. Despite the…

Quantum Gases · Physics 2025-03-04 Ethan C. McGarrigle , Hector D. Ceniceros , Glenn H. Fredrickson

Consider the Langevin process, described by a vector (position,momentum) in $\mathbb{R}^{d}\times\mathbb{R}^d$. Let $\mathcal O$ be a $\mathcal{C}^2$ open bounded and connected set of $\mathbb{R}^d$. We prove the compactness of the…

Probability · Mathematics 2021-09-27 Tony Lelièvre , Mouad Ramil , Julien Reygner

Lefschetz thimbles and complex Langevin dynamics both provide a means to tackle the numerical sign problem prevalent in theories with a complex weight in the partition function, e.g. due to nonzero chemical potential. Here we collect some…

High Energy Physics - Lattice · Physics 2015-06-22 Gert Aarts , Lorenzo Bongiovanni , Erhard Seiler , Denes Sexty

We use a QCD relativistic potential model to compute the strong coupling constant $g$ appearing in the effective Lagrangian which describes the interaction of $0^-$ and $1^-$ $\bar q Q$ states with soft pions in the limit $m_Q \to \infty$.…

High Energy Physics - Phenomenology · Physics 2007-05-23 F. De Fazio

Stabilized Wilson fermions are a reformulation of Wilson clover fermions that incorporates several numerical stabilizing techniques, but also a local change of the fermion action - the original clover term being replaced with an…

High Energy Physics - Lattice · Physics 2022-12-21 Rocco Francesco Basta , Bastian B. Brandt , Francesca Cuteri , Gergely Endrődi , Anthony Francis

We study the problem of stabilizing an unknown partially observable linear time-invariant (LTI) system. For fully observable systems, leveraging an unstable/stable subspace decomposition approach, state-of-art sample complexity is…

Systems and Control · Electrical Eng. & Systems 2025-03-24 Ziyi Zhang , Yorie Nakahira , Guannan Qu

Statistical sampling with the complex Langevin (CL) equation is applied to (0+1)-dimensional Thirring model, and its uniform-field variant, at finite fermion chemical potential $\mu$. The CL simulation reproduces a crossover behavior which…

High Energy Physics - Lattice · Physics 2017-10-25 Hirotsugu Fujii , Syo Kamata , Yoshio Kikukawa

The computational requirements and dynamics of Monte Carlo simulations of unquenched QCD incorporating the infrared quark eigenmodes (up to $\approx \Lambda_{QCD}$) exactly and UV modes via a loop representation are discussed. The accuracy…

High Energy Physics - Lattice · Physics 2015-06-25 A. Duncan , E. Eichten , H. Thacker