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arXiv · 2508.00061

Truncation uncertainties for accurate quantum simulations of lattice gauge theories

Anthony N. Ciavarella·Siddharth Hariprakash·Jad C. Halimeh·Christian W. Bauer
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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 10^{306}.

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Anthony N. Ciavarella, Siddharth Hariprakash, Jad C. Halimeh, Christian W. Bauer. 2025-07-31. Truncation uncertainties for accurate quantum simulations of lattice gauge theories. https://arxiv.org/abs/2508.00061

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