Fluctuations and reweighting of the quark determinant on large lattices

Abstract

We propose to stabilise HMC simulations of lattice QCD with very light Wilson quarks by splitting the quark determinant into two factors and by treating the factor that includes the contribution of the low modes of the Dirac operator as a reweighting factor. In general, determinant reweighting becomes inefficient on large lattices, because the statistical fluctuations of quark determinants increase exponentially with the lattice volume. Random matrix theory and some numerical studies now suggest that the low-mode contribution to the determinant behaves differently, which allows factorisations to be devised that preserve the efficiency of the simulation on large lattices.

7 pages, talk presented at the XXVI International Symposium on Lattice Field Theory, July 14-19, 2008, Williamsburg, Virginia, USA

References in corpus (7)

• Schwarz-preconditioned HMC algorithm for two-flavour lattice QCD
• Stability of lattice QCD simulations and the thermodynamic limit
• Reweighting towards the chiral limit
• Low energy chiral constants from epsilon-regime simulations with improved Wilson fermions
• Lattice QCD with a chirally twisted mass term
• Exploring the epsilon regime with twisted mass fermions
• Unquenched QCD with Light Quarks

Cited by in corpus (7)

• Simulation of QCD with N_f=2+1 flavors of non-perturbatively improved Wilson fermions
• Lattice QCD and the anomalous magnetic moment of the muon
• Status and challenges of simulations with dynamical fermions
• Tuning of the strange quark mass with optimal reweighting
• Sea Contributions to Hadron Electric Polarizabilities through Reweighting
• Determination of $c_{\mathrm{A}}$ in three-flavour lattice QCD with Wilson fermions and tree-level improved gauge action
• Fermions as global correction in lattice QCD