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Probabilistic Hysteresis in Integrable and Chaotic Isolated Hamiltonian Systems
Ralf Bürkle1, Amichay Vardi2, Doron Cohen3
1State Research Center OPTIMAS and Fachbereich Physik, Technische Universität Kaiserslautern, D-67663 Kaiserslautern, Germany.
Physical Review Letters
|October 2, 2019
Summary
Experiments with ultracold atoms reveal how dynamical chaos drives irreversibility. Hysteresis observed in atomic systems demonstrates a failure to return to initial states, offering insights into microscopic irreversibility.
Area of Science:
- Atomic physics
- Quantum chaos
- Statistical mechanics
Background:
- Investigating the microscopic origins of irreversibility is a fundamental challenge in physics.
- Dynamical chaos is a key phenomenon in classical and quantum systems.
Purpose of the Study:
- To propose feasible experiments for studying the onset of irreversibility using ultracold atoms.
- To explore the role of dynamical chaos in microscopic irreversibility.
Main Methods:
- Utilizing small, isolated systems of ultracold atoms.
- Employing a control parameter sweep with a critical value and return.
- Analyzing the probability of atoms failing to return to their initial state (hysteresis).
Main Results:
- Hysteresis is observed as a finite probability of atoms not returning to their initial state.
- Chaotic dynamics during the parameter sweep create distinct features in the final state distribution.
- These features are predicted to be clearly observable in experiments.
Conclusions:
- Dynamical chaos plays a crucial role in the microscopic onset of irreversibility.
- Ultracold atom experiments can provide clear, observable evidence of these effects.
- The proposed experiments offer a novel pathway to study fundamental physics.
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