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Boltzmann-Loschmidt Dispute Reloaded: Quantum 150 Years Later
Leonardo Ermann1, Alexei D Chepelianskii2, Dima L Shepelyansky3
1Departamento de Física Teórica, GIyA, Comisión Nacional de Energía Atómica, Av. del Libertador 8250, Buenos Aires 1429, Argentina.
Entropy (Basel, Switzerland)
|June 26, 2026
Summary
Quantum systems, unlike classical ones, can reverse their evolution perfectly. This research demonstrates that quantum chaos diffusion in cold atoms can be time-reversed with 100% efficiency, challenging classical physics limitations.
Area of Science:
- Quantum physics
- Statistical mechanics
- Atomic physics
Background:
- The Boltzmann-Loschmidt dispute questioned time-reversibility in classical statistical mechanics.
- Classical atomic motion described by time-reversible equations faces challenges with irreversibility.
Purpose of the Study:
- To investigate the time-reversibility of quantum chaos diffusion.
- To explore quantum mechanical solutions to the Boltzmann-Loschmidt paradox.
- To contrast quantum and classical time-reversibility.
Main Methods:
- Analytical calculations of quantum chaos diffusion.
- Numerical simulations of cold atoms/ions in harmonic traps and pulsed optical lattices.
- Investigating the efficiency of time-reversal for quantum evolution.
Main Results:
- Quantum chaos diffusion can be time-reversed with up to 100% efficiency.
- This perfect time-reversibility is demonstrated for cold atoms or ions.
- Classical evolution exhibits exponentially small errors, breaking time-reversibility.
Conclusions:
- Quantum mechanics offers a path to perfect time-reversibility, unlike classical mechanics.
- Experimental techniques are available to demonstrate this quantum perspective on the Boltzmann-Loschmidt dispute.
- The study highlights fundamental differences between quantum and classical descriptions of chaotic systems.
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