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arXiv · 2203.02330

Gluon Digitization via Character Expansion for Quantum Computers

Yao Ji·Henry Lamm·Shuchen Zhu
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Abstract

Efficient digitization is required for quantum simulations of gauge theories. Schemes based on discrete subgroups use a smaller, fixed number of qubits at the cost of systematic errors. We systematize this approach by deriving the single plaquette action through matching the continuous group action to that of a discrete one via group character expansions modulo the field fluctuation contributions. We accompany this scheme by simulations of pure gauge over the largest discrete crystal-like subgroup of $SU(3)$ up to the fifth-order in the coupling constant.

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Yao Ji, Henry Lamm, Shuchen Zhu. 2022-03-04. Gluon Digitization via Character Expansion for Quantum Computers. https://doi.org/10.1103/physrevd.107.114503

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