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Age-dependent Dynamics of Locomotion in Caenorhabditis elegans: A Lyapunov Exponent Analysis
Published on: September 23, 2025
430
Positive quantum Lyapunov exponents in experimental systems with a regular classical limit.
Saúl Pilatowsky-Cameo1, Jorge Chávez-Carlos1, Miguel A Bastarrachea-Magnani2
1Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Apdo. Postal 70-543, C.P. 04510 CDMX, Mexico.
Physical Review. E
|February 20, 2020
Summary
Out-of-time order correlators (OTOCs) can exhibit exponential growth in regular quantum systems, not just chaotic ones. This finding challenges the common assumption linking OTOCs solely to quantum chaos.
Area of Science:
- Quantum physics
- Quantum chaos
- Statistical mechanics
Background:
- Quantum chaos studies signatures of classical chaos in quantum systems.
- Exponential growth of out-of-time order correlators (OTOCs) is often equated with quantum chaos.
- Experimental investigations are exploring OTOCs in systems like the Dicke model.
Purpose of the Study:
- To investigate the behavior of OTOCs in experimentally relevant models.
- To determine if exponential OTOC growth is exclusive to chaotic regimes.
- To clarify the relationship between OTOCs, quantum chaos, and system dynamics.
Main Methods:
- Theoretical analysis of the Dicke model and the Lipkin-Meshkov-Glick model.
- Examination of OTOCs under experimentally accessible parameters.
- Distinguishing between chaos-driven and other sources of exponential behavior.
Main Results:
- Exponential OTOC growth was observed in the regular regime of the Dicke model.
- Similar exponential behavior was found in the integrable Lipkin-Meshkov-Glick model.
- The exponential behavior in these cases originates from unstable stationary points, not classical chaos.
Conclusions:
- The common assumption equating exponential OTOC growth with quantum chaos is not universally valid.
- Exponential OTOC behavior can arise from sources other than chaos, such as unstable stationary points.
- This has significant implications for interpreting experimental results and understanding quantum chaos.
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