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arXiv · 2601.22273

Excited-state uncertainties in lattice-QCD calculations of hadron masses and scattering phase shifts

William Detmold·Anthony V. Grebe·Daniel C. Hackett·Marc Illa·Robert J. Perry·Phiala E. Shanahan·Michael L. Wagman
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Abstract

Lattice QCD has historically produced energy results interpretable as either estimates relying on implicit assumptions about asymptotic behavior or one-sided upper bounds. New Lanczos methods providing two-sided bounds with less-restrictive assumptions are introduced and quantified in a high-statistics calculation with unphysical quark masses. Two-sided bounds without spectral assumptions provide sub-percent constraints on the nucleon mass. Other bounds, which assume all states in a given energy window are resolved, provide meaningful two-sided constraints on nucleon-nucleon scattering phase shifts.

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William Detmold, Anthony V. Grebe, Daniel C. Hackett, Marc Illa, Robert J. Perry, Phiala E. Shanahan, Michael L. Wagman. 2026-01-29. Excited-state uncertainties in lattice-QCD calculations of hadron masses and scattering phase shifts. https://arxiv.org/abs/2601.22273

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