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arXiv · 1507.08916

Massive photons: an infrared regularization scheme for lattice QCD+QED

Michael G. Endres·Andrea Shindler·Brian C. Tiburzi·Andre Walker-Loud
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Abstract

Standard methods for including electromagnetic interactions in lattice quantum chromodynamics calculations result in power-law finite-volume corrections to physical quantities. Removing these by extrapolation requires costly computations at multiple volumes. We introduce a photon mass to alternatively regulate the infrared, and rely on effective field theory to remove its unphysical effects. Electromagnetic modifications to the hadron spectrum are reliably estimated with a precision and cost comparable to conventional approaches that utilize multiple larger volumes. A significant overall cost advantage emerges when accounting for ensemble generation. The proposed method may benefit lattice calculations involving multiple charged hadrons, as well as quantum many-body computations with long-range Coulomb interactions.

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Michael G. Endres, Andrea Shindler, Brian C. Tiburzi, Andre Walker-Loud. 2016-08-11. Massive photons: an infrared regularization scheme for lattice QCD+QED. https://doi.org/10.1103/physrevlett.117.072002

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