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Nonequilibrium free-energy estimation conditioned on measurement outcomes
1Faculty of Physics, Technion - Israel Institute of Technology, Haifa 32000, Israel.
Physical Review. E
|September 28, 2017
Summary
Discarding specific outcomes in Jarzynski equality calculations improves convergence for free-energy differences. This method enhances sampling efficiency in nonequilibrium statistical mechanics, offering a practical advantage.
Area of Science:
- Statistical Mechanics
- Physical Chemistry
- Thermodynamics
Background:
- The Jarzynski equality is a key tool in nonequilibrium statistical mechanics.
- It enables equilibrium free-energy calculations from nonequilibrium work distributions.
- Current methods often face convergence issues due to rare event sampling.
Purpose of the Study:
- To investigate if measurement and feedback enhance convergence in free-energy calculations.
- To explore modifications of the Jarzynski equality for improved efficiency.
Main Methods:
- A modified Jarzynski equality was employed.
- Realizations with specific outcomes were selectively kept, others discarded.
- The impact on convergence was analyzed.
Main Results:
- Discarding unwanted outcomes significantly improved convergence.
- This approach offers better efficiency than standard Jarzynski equality calculations.
- The observed improvement is linked to Bennett's acceptance ratio method.
Conclusions:
- Measurement and feedback, via outcome selection, can enhance Jarzynski equality convergence.
- This offers a practical strategy for more efficient free-energy calculations.
- The findings connect to established methods like Bennett's acceptance ratio.
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