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Maxwell's Demon in Quantum Mechanics.
1Department of Philosophy, The Hebrew University of Jerusalem Mount Scopus, Jerusalem 91905, Israel.
Entropy (Basel, Switzerland)
|December 8, 2020
Summary
Maxwell's Demon is compatible with quantum mechanics, challenging the universality of the Second Law of thermodynamics. This finding suggests the arrow of time may not stem from this fundamental law.
Area of Science:
- Thermodynamics
- Quantum Mechanics
- Statistical Mechanics
Background:
- Maxwell's Demon is a famous thought experiment questioning the Second Law of Thermodynamics.
- The Second Law is often linked to the arrow of time, making its potential violation significant.
- Previous attempts to resolve the paradox, including those based on Landauer's thesis, have been deemed not general enough.
Purpose of the Study:
- To demonstrate that Maxwell's Demon is compatible with quantum mechanics.
- To analyze a specific experimental setup that violates the Second Law within a quantum framework.
- To explore the quantum mechanical underpinnings of measurement, erasure, and macrostates.
Main Methods:
- Analysis of a specific, idealized experimental setup within standard quantum mechanics.
- Development of two distinct arguments, one with and one without the projection postulate.
- Investigation of the relationship between measurement and erasure in quantum systems.
Main Results:
- Demonstration that Maxwell's Demon is compatible with quantum mechanics.
- Proof that the analyzed quantum experimental setup violates the Second Law of Thermodynamics.
- Identification of quantum mechanical counterparts to classical macrostates, explaining the Demon's efficacy at both micro and macro levels.
Conclusions:
- The Second Law of Thermodynamics is not universally applicable.
- The arrow of time cannot be solely explained by the Second Law.
- Further investigation is needed to find alternative explanations for temporal directionality.
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