Truncation uncertainties for accurate quantum simulations of lattice gauge theories

ORAL

Abstract

The encoding of lattice gauge theories onto quantum computers requires a discretization of the gauge field's Hilbert space on each link, which presents errors with respect to the Kogut--Susskind limit. In the electric basis, Hilbert space fragmentation has recently been shown to limit the excitation of large electric fields. Here, we leverage this to develop a formalism for estimating the size of truncation errors in the electric basis. Generically, the truncation error falls off as a factorial of the field truncation. Examples of this formalism are applied to the Schwinger model and a pure U(1) lattice gauge theory. For reasonable choices of parameters, we improve on previous error estimates by a factor of 10306.

*We would like to acknowledge useful conversations with Jesse Stryker, Ivan Burbano, Irian D'Andrea, Neel Modi, Chris Kane, and helpful feedback from John Preskill. A.N.C, S.H. and C.W.B. acknowledge funding through the U.S. Department of Energy (DOE), Office of Science under contract DE-AC02-05CH11231, partially through Quantum Information Science Enabled Discovery (QuantISED) for High Energy Physics (KA2401032). Additional support is acknowledged from the U.S. Department of Energy, Office of Science, National Quantum Information Science Research Centers, Quantum Systems Accelerator. J.C.H. acknowledges funding by the Max Planck Society, the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's Excellence Strategy – EXC-2111 – 390814868, and the European Research Council (ERC) under the European Union's Horizon Europe research and innovation program (Grant Agreement No. 101165667)—ERC Starting Grant QuSiGauge. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Council Executive Agency. Neither the European Union nor the granting authority can be held responsible for them. This work is part of the Quantum Computing for High-Energy Physics (QC4HEP) working group.

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Publication: arXiv:2508.00061

Presenters

  • Anthony N Ciavarella

    • Lawrence Berkeley National Lab

Authors

  • Anthony N Ciavarella

    • Lawrence Berkeley National Lab

  • Jad C. Halimeh

    • Ludwig Maximillian University of Munich
    • Max Planck Institute of Quantum Optics

  • Siddharth Hariprakash

    • BlueQubit. UC Berkeley, LBNL
    • Lawrence Berkeley National Laboratory
    • UC Berkeley, LBNL, BlueQubit Inc.

  • Christian W Bauer

    • Lawrence Berkeley National Laboratory