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602
Universal exponent for transport in mixed Hamiltonian dynamics.
Or Alus1, Shmuel Fishman1, James D Meiss2
1Physics Department Technion-Israel Institute of Technology Haifa 3200, Israel.
Physical Review. E
|January 20, 2018
Summary
We found that transport in mixed dynamical systems follows a power-law decay, supporting the Meiss-Ott Markov tree model for chaotic transport. This model accurately describes trajectory survival probabilities in complex phase spaces.
Area of Science:
- Dynamical systems theory
- Statistical mechanics
- Chaos theory
Background:
- Transport in mixed phase space is complex.
- Understanding chaotic transport is crucial in various scientific fields.
- Previous models struggled to capture the nuances of transport near hierarchical structures.
Purpose of the Study:
- To compute universal distributions for transition probabilities in a Markov model for transport.
- To verify the applicability of the Meiss-Ott Markov tree model to mixed systems.
- To analyze the survival probability distribution of trajectories in complex phase spaces.
Main Methods:
- Developed a Markov model for transport in area-preserving maps.
- Analyzed transition probabilities within the mixed phase space.
- Computed survival probability distributions for trajectories near island-around-island hierarchies.
- Compared results with simulations of the Hénon and Chirikov-Taylor maps.
Main Results:
- Universal distributions for transition probabilities were computed.
- A power-law decay with exponent γ=1.57 was observed for survival probabilities.
- This exponent aligns with simulation results from the Hénon and Chirikov-Taylor maps.
- The observed power-law decay provides strong evidence for the Meiss-Ott Markov tree model.
Conclusions:
- The Meiss-Ott Markov tree model effectively describes transport in mixed dynamical systems.
- The universal power-law decay is a key characteristic of chaotic transport in these systems.
- This study validates a theoretical model using computational and simulation approaches.
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