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Updated: May 18, 2026
11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Universality classes of transport in time-dependent random potentials.
Yevgeny Krivolapov1, Shmuel Fishman
1Physics Department, Technion-Israel Institute of Technology, Haifa 32000, Israel.
Summary
Classical particles in random potentials exhibit uniform acceleration at low velocities, transitioning to anomalous diffusion. This study analyzes this behavior using the Fokker-Planck approximation, revealing distinct universality classes for different dimensions.
Area of Science:
- Statistical physics
- Quantum optics
- Chaos theory
Background:
- Investigates particle dynamics under random spatio-temporal potentials.
- Relevant to recent experiments in optics and atom optics.
Purpose of the Study:
- Analyze the growth of average kinetic energy for classical particles.
- Characterize anomalous diffusion regimes and universality classes.
Main Methods:
- Utilized the Fokker-Planck approximation.
- Expressed diffusion coefficient via power spectral density (Fourier transform of potential correlation).
- Established scaling forms and computed velocity limits.
Main Results:
- Identified uniform acceleration at low velocities and anomalous diffusion at later stages.
- Classified random potentials into universality classes based on diffusion behavior.
- Demonstrated a rich variety of universality classes in 1D systems versus higher dimensions.
Conclusions:
- The study provides a framework for understanding particle dynamics in random potentials.
- Highlights the dimensional dependence of universality classes.
- Connects the findings to Chirikov resonances in chaos theory.
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