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Distribution- versus correlation-induced anomalous transport in quenched random velocity fields
1Spanish National Research Council (IDÆA-CSIC), Barcelona 08034, Spain. marco.dentz@idaea.csic.es
Physical Review Letters
|January 15, 2011
Summary
Anomalous transport in random media arises from disorder, but different mechanisms cause similar scaling laws. Spatial particle densities and first passage times reveal the distinct origins of this anomalous transport.
Area of Science:
- Physics
- Statistical Mechanics
- Condensed Matter Physics
Background:
- Anomalous transport is observed in various complex systems.
- Disorder in media significantly impacts particle movement.
- Understanding scaling laws is crucial for characterizing transport phenomena.
Purpose of the Study:
- To investigate the mechanisms behind anomalous transport in quenched random media.
- To differentiate between mechanisms causing similar anomalous scaling laws.
- To identify indicators for distinguishing the origins of anomalous transport.
Main Methods:
- Analysis of broad disorder point distributions.
- Study of strong disorder correlations.
- Examination of spatial particle densities.
- Investigation of first passage time distributions.
Main Results:
- Broad disorder and strong correlations can lead to identical anomalous scaling laws for particle displacement mean and variance.
- The underlying mechanisms for these identical scaling laws are fundamentally different.
- Spatial particle densities and first passage time distributions serve as discriminators.
Conclusions:
- Anomalous transport in quenched random media has diverse underlying mechanisms.
- Distinctive signatures in particle densities and first passage times are key to identifying these mechanisms.
- This research provides a method to distinguish between different origins of anomalous transport.
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