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Updated: Nov 27, 2025
11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
8.8K
Thermodynamics at Very Long Time and Space Scales.
Bjarne Andresen1, Christopher Essex2
1Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, DK-2100 Copenhagen Ø, Denmark.
Entropy (Basel, Switzerland)
|December 8, 2020
Summary
Exploring extremely large time and length scales, this study introduces "slow time" physics. Key findings include the disappearance of temperature and the emergence of a new entropy component due to long-term averaging.
Area of Science:
- Thermodynamics and Statistical Mechanics
- Physics of Complex Systems
- Scale-dependent Physics
Background:
- Classical and quantum physics rely on observer-dependent time and length scales.
- Laboratory-scale concepts (volume, pressure, temperature) evolved from human-centric scales.
- Recent advances probe molecular and nanosecond scales, necessitating new physical concepts.
Purpose of the Study:
- To investigate physical concepts at extremely large time and length scales, termed "slow time."
- To determine the applicability of existing laboratory concepts in the "slow time" regime.
- To identify new physical concepts that may emerge at these vast scales.
Main Methods:
- Conceptual exploration of physics under conditions of extremely long timescales.
- Analysis of how established thermodynamic quantities behave with reduced temporal resolution.
- Development of theoretical frameworks for scale-dependent physical phenomena.
Main Results:
- Temperature is found to be an inapplicable concept in the "slow time" regime.
- A novel component of entropy emerges from the long-time averaging of other physical quantities.
- The study reveals a loss of temporal resolution as a key characteristic of "slow time."
Conclusions:
- Physics at extremely large scales requires a re-evaluation of fundamental concepts.
- "Slow time" physics introduces new phenomena, such as emergent entropy components.
- Scale-dependent thermodynamics offers a framework for understanding systems with vastly different temporal resolutions.
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