Approximate Optimal Controls via Instanton Expansion for Low Temperature Free Energy Computation

  title={Approximate Optimal Controls via Instanton Expansion for Low Temperature Free Energy Computation},
  author={Gr'egoire Ferr'e and Tobias Grafke},
  journal={arXiv: Statistical Mechanics},
The computation of free energies is a common issue in statistical physics. A natural technique to compute such high dimensional integrals is to resort to Monte Carlo simulations. However these techniques generally suffer from a high variance in the low temperature regime, because the expectation is dominated by high values corresponding to rare system trajectories. A standard way to reduce the variance of the estimator is to modify the drift of the dynamics with a control enhancing the… 

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