Local coherence and deflation of the low quark modes in lattice QCD
نویسندگان
چکیده
منابع مشابه
Local coherence and deflation of the low quark modes in lattice QCD
The spontaneous breaking of chiral symmetry in QCD is known to be linked to a non-zero density of eigenvalues of the massless Dirac operator near the origin. Numerical studies of two-flavour QCD now suggest that the low quark modes are locally coherent to a certain extent. As a consequence, the modes can be simultaneously deflated, using local projectors, with a total computational effort propo...
متن کاملDeflation acceleration of lattice QCD simulations
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 propagated along the field trajectories generated by the Hybrid Monte Carlo (HMC) algorithm with a modest effort. The quark forces that drive the simulation ma...
متن کاملDeflation of Eigenvalues for GMRES in Lattice QCD
This paper looks at the iterative solution of complex, non-Hermitian systems of linear equations associated with a lattice QCD problem in particle physics. Let the n by n system of equations be Ax = b. We use a version of the GMRES method that deflates eigenvalues and can solve systems with multiple right-hand sides. We give examples that show deflating eigenvalues can make a significant improv...
متن کاملDeflation of Eigenvalues for Iterative Methods in Lattice QCD
Work on generalizing the deflated, restarted GMRES algorithm, useful in lattice studies using stochastic noise methods, is reported. We first show how the multi-mass extension of deflated GMRES can be implemented. We then give a deflated GMRES method that can be used on multiple right-hand sides of Ax = b in an efficient manner. We also discuss and give numerical results on the possibilty of co...
متن کاملQuark Model From Lattice QCD
We study the valence approximation in lattice QCD of hadrons where the cloud quarks and antiquarks are deleted by truncating the backward time propagation (Z graphs) in the connected insertions. Whereas, the sea quarks are eliminated via the quenched approximation and in the disconnected insertions. It is shown that the ratios of isovector to isoscalar matrix elements in the nucleon reproduce t...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of High Energy Physics
سال: 2007
ISSN: 1029-8479
DOI: 10.1088/1126-6708/2007/07/081