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Related papers: Physics issues in simulations with dynamical overl…

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I show how to avoid a two level nested conjugate gradient procedure in the context of Hybrid Monte Carlo with the overlap fermionic action. The resulting procedure is quite similar to Hybrid Monte Carlo with domain wall fermions, but is…

High Energy Physics - Lattice · Physics 2016-08-25 Herbert Neuberger

We introduce a numerical algorithm to stochastically sample the dual fermion perturbation series around the dynamical mean field theory, generating all topologies of two-particle interaction vertices. We show results in the weak and strong…

Strongly Correlated Electrons · Physics 2016-07-07 Sergei Iskakov , Andrey E. Antipov , Emanuel Gull

I summarize the physics results obtained from large-scale dynamical overlap fermion simulations by the JLQCD and TWQCD collaborations. The numerical simulations are performed at a fixed global topological sector; the physics results in the…

High Energy Physics - Lattice · Physics 2010-01-21 Shoji Hashimoto

The use of APE smearing or other blocking techniques in lattice fermion actions can provide many advantages. There are many variants of these fat link actions in lattice QCD currently, such as FLIC fermions. The FLIC fermion formalism makes…

High Energy Physics - Lattice · Physics 2010-03-04 Waseem Kamleh , Derek B. Leinweber , Anthony G. Williams

We test the scaling behaviour of Wilson, hypercube, maximally twisted mass and overlap fermion actions in dynamical simulations of the 2-dimensional massive Schwinger model. We also present possibilities to simulate overlap fermions…

High Energy Physics - Lattice · Physics 2007-05-23 Nils Christian , Karl Jansen , Kei-ichi Nagai , Beatrix Pollakowski

An algorithm for separating the high- and low-frequency molecular dynamics modes in Hybrid Monte Carlo simulations of gauge theories with dynamical fermions is presented. The separation is based on splitting the pseudo-fermion action into…

High Energy Physics - Lattice · Physics 2008-11-26 A. Ali Khan , T. Bakeyev , M. Göckeler , R. Horsley , D. Pleiter , P. Rakow , A. Schäfer , G. Schierholz , H. Stüben

I discuss the behaviour of algorithms for dynamical fermions as the sea-quark mass decreases. I focus on the Hybrid-Monte-Carlo (HMC) algorithm applied to two degenerate flavours of Wilson fermions. First, I briefly review the performance…

High Energy Physics - Lattice · Physics 2009-11-10 Martin Hasenbusch

We describe an HMC algorithm for dynamical overlap fermions which makes use of their good chiral properties. We test the algorithm in the Schwinger model. Topological sectors are readily changed even in the massless case.

High Energy Physics - Lattice · Physics 2007-05-23 Achim Bode , Urs M. Heller , Robert G. Edwards , Rajamani Narayanan

Current dynamical overlap fermion hybrid Monte Carlo simulations encounter large fermionic forces when there is mixing between near zero-eigenvectors of the kernel operator. This leads to low acceptance rates when there is a large density…

High Energy Physics - Lattice · Physics 2009-03-12 Nigel Cundy

A scheme for separating the high- and low-frequency molecular dynamics modes in Hybrid Monte Carlo (HMC) simulations of gauge theories with dynamical fermions is presented. The algorithm is tested in the Schwinger model with Wilson…

High Energy Physics - Lattice · Physics 2019-08-14 Mike Peardon , James Sexton

The advantages of using Multi-Step corrections for simulations of lattice gauge theories with dynamical fermions will be discussed. This technique is suited for algorithms based on the Multi-Boson representation of the dynamical fermions as…

High Energy Physics - Lattice · Physics 2008-11-26 Enno E. Scholz , Istvan Montvay

There has been much recent progress in the understanding and reduction of the computational cost of the Hybrid Monte Carlo algorithm for Lattice QCD as the quark mass parameter is reduced. In this letter we present a new solution to this…

High Energy Physics - Lattice · Physics 2008-11-26 M. A. Clark , A. D. Kennedy

This is the write-up of three lectures on algorithms for dynamical fermions that were given at the ILFTN workshop 'Perspectives in Lattice QCD' in Nara during November 2005. The first lecture is on the fundamentals of Markov Chain Monte…

High Energy Physics - Lattice · Physics 2012-02-24 A. D. Kennedy

We discuss algorithms for domain wall fermions focussing on accelerating Hybrid Monte Carlo sampling of gauge configurations. Firstly a new multigrid algorithm for domain wall solvers and secondly a domain decomposed hybrid monte carlo…

High Energy Physics - Lattice · Physics 2022-04-01 Peter A Boyle , Dennis Bollweg , Christopher Kelly , Azusa Yamaguchi

I apply a recently developed algorithm for reweighting simulations of lattice QCD from one quark mass to another to simulations performed with overlap fermions in the epsilon regime. I test it by computing the condensate from distributions…

High Energy Physics - Lattice · Physics 2009-01-08 Thomas DeGrand

The Hybrid Monte Carlo (HMC) algorithm currently is the favorite scheme to simulate quantum chromodynamics including dynamical fermions. In this talk-which is intended for a non-expert audience--I want to bring together methodical and…

High Energy Physics - Lattice · Physics 2009-10-30 Thomas Lippert

The improvement of simulations of QCD with dynamical Wilson fermions by combining the Hybrid Monte Carlo algorithm with parallel tempering is studied. As an indicator for decorrelation the topological charge is used.

High Energy Physics - Lattice · Physics 2007-05-23 H. Stüben

We propose a modification of the Hybrid-Monte-Carlo algorithm that allows for a larger step-size of the integration scheme at constant acceptance rate. The key ingredient is that the pseudo-fermion action is split into two parts. We test…

High Energy Physics - Lattice · Physics 2009-11-07 Martin Hasenbusch

We study the opportunities for parallelism for the simulation of surface reactions. We introduce the concept of a partition and we give new simulation methods based on Cellular Automaton using partitions. We elaborate on the advantages and…

Computational Physics · Physics 2007-05-23 S. V. Nedea , J. J. Lukkien , A. P. J. Jansen , P. A. J. Hilbers

The Hybrid Monte Carlo algorithm for the simulation of QCD with dynamical staggered fermions is compared with Kramers equation algorithm. We find substantially different autocorrelation times for local and nonlocal observables. The…

High Energy Physics - Lattice · Physics 2009-10-28 M. E. Berbenni-Bitsch , A. P. Gottlob , S. Meyer , M. Puetz