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Information-theoretic equilibration: the appearance of irreversibility under complex quantum dynamics
Cozmin Ududec1, Nathan Wiebe, Joseph Emerson
1Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario N2L3G1, Canada and Institute for Quantum Computing, 200 University Avenue West, Waterloo, Ontario N2L3G1, Canada.
Physical Review Letters
|September 10, 2013
Summary
Irreversibility emerges in complex quantum systems due to internal dynamics and data limitations, not just decoherence. This finding offers a new perspective on the emergence of time
Area of Science:
- Quantum mechanics
- Statistical mechanics
- Foundations of physics
Background:
- The emergence of irreversibility from reversible microscopic laws is a fundamental problem in physics.
- Existing explanations often rely on decoherence or coarse-graining, which may not apply universally.
Purpose of the Study:
- To describe a novel mechanism for the emergence of irreversibility in coherent, isolated quantum systems.
- To demonstrate that irreversibility can be a typical phenomenon under specific conditions.
Main Methods:
- Theoretical analysis of isolated quantum systems in pure states.
- Incorporation of information-theoretic constraints related to measurement data collection.
- Numerical simulations on model systems.
- Proof of typicality under the random-matrix conjecture.
Main Results:
- A mechanism for irreversibility is presented that does not require decoherence or coarse-graining.
- Irreversibility is shown to be a typical behavior for complex quantum systems.
- The findings apply to coherent, isolated systems in pure quantum states.
Conclusions:
- Irreversibility can emerge generically in quantum mechanics through complex internal dynamics and practical measurement limitations.
- This provides a distinct perspective on irreversibility, complementary to decoherence-based approaches.
- The results are validated numerically and theoretically for complex quantum systems.
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