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Quantum solution to the arrow-of-time dilemma
1QUIT, Dip. A. Volta, 27100 Pavia, Italy.
Physical Review Letters
|October 2, 2009
Summary
Physics can only study phenomena that leave information, meaning entropy must increase or stay constant. Processes with decreasing entropy leave no trace, making them unobservable and the second law of thermodynamics a tautology.
Area of Science:
- Physics
- Thermodynamics
- Quantum Mechanics
Background:
- The arrow-of-time dilemma highlights the conflict between time-invariant physical laws and everyday observations of increasing entropy.
- Understanding the directionality of time in physical processes is a fundamental challenge.
Purpose of the Study:
- To resolve the arrow-of-time dilemma within a quantum mechanical framework.
- To establish the conditions under which physical phenomena are observable.
Main Methods:
- Analysis of phenomena within a quantum mechanical framework.
- Investigation of the relationship between information trails and entropy changes.
Main Results:
- Phenomena leaving information traces necessitate constant or increasing entropy.
- Processes with decreasing entropy leave no observable information, rendering them indistinguishable from non-occurrence.
Conclusions:
- The second law of thermodynamics becomes a tautology when considering observable phenomena.
- Physics is inherently limited to studying processes where entropy does not decrease.
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