Fast free-energy estimation for complex systems with nonreversible simulated tempering

Yoshihiko Nishikawa; Koji Hukushima

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arXiv · 2610.08598

Fast free-energy estimation for complex systems with nonreversible simulated tempering

Yoshihiko Nishikawa·Koji Hukushima

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Abstract

We discuss free-energy estimation for complex systems using simulated tempering with Wang--Landau-type feedback. We show that introducing nonreversible dynamics in temperature space and multiple temperature updates per step significantly accelerates the convergence of the free-energy estimate. We then apply the algorithm to the three-dimensional Edwards-Anderson spin-glass model. Our results show that the algorithm can precisely estimate the free energy up to a large system size $L \simeq 64$, and that subsequent equilibrium simulated tempering simulations with the estimated free energy can rapidly sample from the Boltzmann distributions over a wide temperature range that covers the spin-glass transition temperature. The convergence time of our algorithm grows much more slowly with system size than that of another known algorithm for on-the-fly free-energy estimation.

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Yoshihiko Nishikawa, Koji Hukushima. 2026-10-06. Fast free-energy estimation for complex systems with nonreversible simulated tempering. https://arxiv.org/abs/2610.08598

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