MORE Thermal Gauge Theories at Finite $\theta$ and $\mu$ from Real-Time Quantum Simulation

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-$(T,\theta,\mu)$ 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.