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Related papers: Deflation Methods in Fermion Inverters

200 papers

I review recent developments in lattice QCD. I first give an overview of its formalism, and then discuss lattice discretizations of fermions. We then turn to a description of the quenched approximation and why it is disappearing as a…

High Energy Physics - Phenomenology · Physics 2014-11-17 Thomas DeGrand

The quaternion biconjugate gradient (QBiCG) method, as a novel variant of quaternion Lanczos-type methods for solving the non-Hermitian quaternion linear systems, does not yield a minimization property. This means that the method possesses…

Numerical Analysis · Mathematics 2024-02-07 Tao Li , Qing-Wen Wang , Xin-Fang Zhang

A lot of effort in lattice simulations over the last years has been devoted to studies of the QCD deconfinement transition. Most state-of-the-art simulations use rooted staggered fermions, while Wilson fermions are affected by large…

High Energy Physics - Lattice · Physics 2011-01-27 Bastian B. Brandt , Owe Philipsen , Hartmut Wittig , Lars Zeidlewicz

In this paper, two efficient iterative algorithms based on the simpler GMRES method are proposed for solving shifted linear systems. To make full use of the shifted structure, the proposed algorithms utilizing the deflated restarting…

Numerical Analysis · Mathematics 2021-07-26 Hong-Xiu Zhong , Xian-Ming Gu

A new approach is discussed for solving large nonsymmetric systems of linear equations with multiple right-hand sides. The first system is solved with a deflated GMRES method that generates eigenvector information at the same time that the…

Mathematical Physics · Physics 2007-05-23 Ronald B. Morgan , Walter Wilcox

The recent introduction of a deformed non-minimal version of the noncommutative Standard Model in the enveloping-algebra approach, having a one-loop renormalisable gauge sector involving a higher order gauge term, motivates us to consider…

High Energy Physics - Theory · Physics 2010-04-30 C. Tamarit , J. Trampetic

The numerical and computational aspects of the overlap formalism in lattice quantum chromodynamics are extremely demanding due to a matrix-vector product that involves the sign function of the hermitian Wilson matrix. In this paper we…

High Energy Physics - Lattice · Physics 2009-11-07 J. van den Eshof , A. Frommer , Th. Lippert , K. Schilling , H. A. van der Vorst

We discuss the successes and limitations of statistical sampling for a sequence of models studied in the context of lattice QCD and emphasize the need for new methods to deal with finite-density and real-time evolution. We show that these…

High Energy Physics - Lattice · Physics 2022-09-21 Yannick Meurice , Ryo Sakai , Judah Unmuth-Yockey

Within the framework of quenched lattice QCD and using O(a) improved Wilson fermions and non-perturbative renormalisation, a high statistics computation of low moments of the unpolarised nucleon structure functions is given. Particular…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Göckeler , R. Horsley , D. Pleiter , P. E. L. Rakow , G. Schierholz

We discuss how the peculiar properties of maximally twisted Wilson fermions can be exploited to set up a consistent LQCD computational scheme in which the CP-conserving matrix elements of the $\Delta S =1,2$ effective weak Hamiltonian can…

High Energy Physics - Lattice · Physics 2016-09-01 Roberto Frezzotti , Giancarlo Rossi

In this paper, we propose the global quaternion full orthogonalization (Gl-QFOM) and global quaternion generalized minimum residual (Gl-QGMRES) methods, which are built upon global orthogonal and oblique projections onto a quaternion matrix…

Numerical Analysis · Mathematics 2023-08-28 Tao Li , Qing-Wen Wang , Xin-Fang Zhang

We present our result for the $K\to\pi\pi$ decay amplitudes for both the $\Delta I=1/2$ and $3/2$ processes with the improved Wilson fermion action. Expanding on the earlier works by Bernard {\it et al.} and by Donini {\it et al.}, we show…

High Energy Physics - Lattice · Physics 2015-10-14 N. Ishizuka , K. -I. Ishikawa , A. Ukawa , T. Yoshié

We present a multi-level algorithm for the solution of five dimensional chiral fermion formulations, including domain wall and Mobius Fermions. The algorithm operates on the red-black preconditioned Hermitian operator, and directly…

High Energy Physics - Lattice · Physics 2014-02-12 P A Boyle

These notes aim to provide a pedagogical introduction to Lattice QCD. The topics covered include the scope of LQCD calculations, lattice discretization of gauge and fermion (naive, Wilson, and staggered) actions, doubling problem, improved…

High Energy Physics - Lattice · Physics 2007-05-23 Rajan Gupta

Lattice fermions with suppressed high momentum modes solve the ultraviolet slowing down problem in lattice QCD. This paper describes a stochastic evaluation of the effective action of such fermions. The method is a based on the Lanczos…

High Energy Physics - Lattice · Physics 2008-11-26 Artan Borici

The solution of large scale Sylvester matrix equation plays an important role in control and large scientific computations. A popular approach is to use the global GMRES algorithm. In this work, we first consider the global GMRES algorithm…

Numerical Analysis · Mathematics 2017-06-06 Najmeh Azizi Zadeh , Azita Tajaddini , Gang Wu

We investigate the QCD Anderson transition by studying the low-lying eigenmodes of the overlap operator in the background of gauge configurations with 2+1+1 quark flavors of twisted-mass Wilson fermions. The mobility edge, below which…

High Energy Physics - Lattice · Physics 2025-03-05 Robin Kehr , Lorenz von Smekal

In this paper the modification of the method conventionally used for the modeling of the massive fermions production and decays is proposed. The step by step algorithm is presented. Under the strict conditions the proposed method of…

High Energy Physics - Phenomenology · Physics 2008-04-02 A. A. Ashimova , S. R. Slabospitsky

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

When lattice QCD is formulated in sectors of fixed quark numbers, the canonical fermion determinants can be expressed explicitly in terms of transfer matrices. This in turn provides a complete factorization of the fermion determinants in…

High Energy Physics - Lattice · Physics 2023-02-16 Urs Wenger