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Long-ranged correlations in large deviations of local clustering
Jakub Dolezal1, Robert L Jack1,2
1DAMTP, University of Cambridge, Centre for Mathematical Sciences, Wilberforce Road, Cambridge CB3 0WA, United Kingdom.
Physical Review. E
|June 17, 2021
Summary
We studied particle clustering in diffusing systems, finding that biasing one particle causes a system-wide response. This response impacts large-deviation events and system dynamics, even when biasing two particles.
Area of Science:
- Statistical Physics
- Complex Systems
- Non-equilibrium Dynamics
Background:
- Understanding particle clustering is crucial in various physical systems.
- Investigating large deviations reveals rare but significant system behaviors.
- Macroscopic fluctuation theory provides a framework for non-equilibrium systems.
Purpose of the Study:
- To analyze large deviations of particle clustering around a single particle.
- To understand how a local bias on one particle affects the entire system.
- To explore the consequences of biasing two particles in such systems.
Main Methods:
- Focus on biased ensembles of trajectories to realize large-deviation events.
- Application of macroscopic fluctuation theory.
- Analysis of the coupling between bias and hydrodynamic modes.
Main Results:
- A local bias on a single particle induces a long-ranged response across the system.
- Dynamical free energy exhibits non-trivial scaling with system size in 1 and 2 dimensions.
- Biasing two particles also leads to observable consequences.
Conclusions:
- The study elucidates the collective response to local perturbations in diffusing particle systems.
- Findings highlight the importance of hydrodynamic modes in mediating system-wide effects.
- The research provides insights into the statistical mechanics of non-equilibrium systems.
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