Truncation uncertainties for accurate quantum simulations of lattice gauge theories

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}.

arXiv:2508.00061 [quant-ph]

(or arXiv:2508.00061v4 [quant-ph] for this version)

https://doi.org/10.48550/arXiv.2508.00061 Focus to learn more arXiv-issued DOI via DataCite

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