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arXiv · 2110.15375

Approaching the master-field: Hadronic observables in large volumes

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

The master-field approach to lattice QCD envisions performing calculations on a small number of large-volume gauge-field configurations. Substantial progress has been made recently in the generation of such fields, and this must be joined with measurement strategies that take advantage of the large volume. In these proceedings, we describe how to compute simple hadronic quantities efficiently and estimate their errors in the master-field approach, i.e. by studying cross-correlations of observables on a single configuration. We discuss the scaling of the uncertainty with the volume and compare extractions based on momentum-projected and position-space two-point functions. The latter show promising results, already at intermediate volumes, but come with additional technical complexities such as a more complicated manifestation of boundary effects, which we also address.

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Marco Cè, Mattia Bruno, John Bulava, Anthony Francis, Patrick Fritzsch, Jeremy R. Green, Maxwell T. Hansen, Antonio Rago. 2021-10-28. Approaching the master-field: Hadronic observables in large volumes. https://doi.org/10.22323/1.396.0383

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