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arXiv · 1906.11213

Gluon Field Digitization for Quantum Computers

Andrei Alexandru·Paulo F. Bedaque·Siddhartha Harmalkar·Henry Lamm·Scott Lawrence·Neill C. Warrington
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Abstract

Simulations of gauge theories on quantum computers require the digitization of continuous field variables. Digitization schemes that uses the minimum amount of qubits are desirable. We present a practical scheme for digitizing $SU(3)$ gauge theories via its discrete subgroup $S(1080)$. The $S(1080)$ standard Wilson action cannot be used since a phase transition occurs as the coupling is decreased, well before the scaling regime. We proposed a modified action that allows simulations in the scaling window and carry out classical Monte Carlo calculations down to lattice spacings of order $a\approx 0.08$ fm. We compute a set of observables with sub-percent precision at multiple lattice spacings and show that the continuum extrapolated value agrees with the full $SU(3)$ results. This suggests that this digitization scheme provides sufficient precision for NISQ-era QCD simulations.

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Andrei Alexandru, Paulo F. Bedaque, Siddhartha Harmalkar, Henry Lamm, Scott Lawrence, Neill C. Warrington. 2019-06-26. Gluon Field Digitization for Quantum Computers. https://doi.org/10.1103/physrevd.100.114501

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