Variance reduction with practical all-to-all lattice propagators

Abstract

We discuss all-to-all quark propagator techniques in two (related) contexts within Lattice QCD: the computation of closed quark propagators, and applications to the so-called "eye diagrams" appearing in the computation of non-leptonic kaon decay amplitudes. Combinations of low-mode averaging and diluted stochastic volume sources that yield optimal signal-to-noise ratios for the latter problem are developed. We also apply a recently proposed probing algorithm to compute directly the diagonal of the inverse Dirac operator, and compare its performance with that of stochastic methods. At fixed computational cost the two procedures yield comparable signal-to-noise ratios, but probing has practical advantages which make it a promising tool for a wide range of applications in Lattice QCD.

26 pages, 11 figures. Published version

References in corpus (5)

• Electromagnetic form factor of the pion from twisted-mass lattice QCD at Nf=2
• Evaluation of disconnected quark loops for hadron structure using GPUs
• Probing the chiral regime of Nf=2 QCD with mixed actions
• K-->pipi amplitudes from lattice QCD with a light charm quark
• Exploring the role of the charm quark in the $\Delta I=1/2$ rule

Cited by in corpus (5)

• Uncertainty Quantification in Lattice QCD Calculations for Nuclear Physics
• Evaluating topological charge density with symmetric multi-probing method
• A multigrid accelerated eigensolver for the Hermitian Wilson-Dirac operator in lattice QCD
• Exploring the role of the charm quark in the $\Delta I=1/2$ rule
• Disconnected hadronic vacuum polarization contribution to the muon g-2 with HISQ