MORE Thermal Gauge Theories at Finite $θ$ and $μ$ from Real-Time Quantum Simulation

Henry Lamm

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arXiv · 2609.38569

MORE Thermal Gauge Theories at Finite $θ$ and $μ$ from Real-Time Quantum Simulation

Henry Lamm

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Abstract

Imaginary-time evolution can be reconstructed from real-time quantum simulations using exact integral transforms. We identify the construction of Guo, Shibu, Lin, and Zhao as a continuous linear combination of Hamiltonian simulations and show that its slow $1/t_{\rm cut}$ convergence arises from a redundant kernel component. We extend the construction from pure-state matrix elements to thermal traces and correlators. One real-time dataset then reconstructs targeted inverse temperatures, Euclidean separations, and chemical potentials through classical post-processing, bringing finite-$(T,θ,μ)$ physics within reach of real-time quantum simulation without thermal-state preparation. We benchmark the method on one- and two-flavor lattice Schwinger models, including circuit-level simulations with depolarizing noise.

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Henry Lamm. 2026-09-29. MORE Thermal Gauge Theories at Finite $θ$ and $μ$ from Real-Time Quantum Simulation. https://arxiv.org/abs/2609.38569

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