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arXiv · 2307.15674

Exploiting stochastic locality in lattice QCD: hadronic observables and their uncertainties

Mattia Bruno·Marco Cè·Anthony Francis·Patrick Fritzsch·Jeremy R. Green·Maxwell T. Hansen·Antonio Rago
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Abstract

Because of the mass gap, lattice QCD simulations exhibit stochastic locality: distant regions of the lattice fluctuate independently. There is a long history of exploiting this to increase statistics by obtaining multiple spatially-separated samples from each gauge field; in the extreme case, we arrive at the master-field approach in which a single gauge field is used. Here we develop techniques for studying hadronic observables using position-space correlators, which are more localized, and compare with the standard time-momentum representation. We also adapt methods for estimating the variance of an observable from autocorrelated Monte Carlo samples to the case of correlated spatially-separated samples.

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Mattia Bruno, Marco Cè, Anthony Francis, Patrick Fritzsch, Jeremy R. Green, Maxwell T. Hansen, Antonio Rago. 2023-07-28. Exploiting stochastic locality in lattice QCD: hadronic observables and their uncertainties. https://doi.org/10.1007/jhep11(2023)167

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