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Heat fluctuations in chemically active systems.
Joël Mabillard1, Christoph A Weber2, Frank Jülicher1,3,4
1Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Straße 38, 01187, Dresden, Germany.
Physical Review. E
|February 17, 2023
Summary
Active fluctuations in living systems, driven by chemical heat, dominate thermal fluctuations on large scales. This study provides a framework to understand these active systems and their fluctuations.
Area of Science:
- Biophysics
- Statistical Mechanics
- Chemical Physics
Background:
- Living cells are chemically active systems maintained out of thermal equilibrium.
- Chemical events generate heat, leading to active fluctuations.
- Understanding the scales of active vs. thermal fluctuations is crucial.
Purpose of the Study:
- To formulate a theoretical framework for heat fluctuations in active systems.
- To determine the length and time scales where active fluctuations dominate thermal fluctuations.
- To characterize the distinct behaviors of active and thermal fluctuations.
Main Methods:
- Development of a stochastic field theory.
- Inclusion of Poisson white noise to model heat fluctuations.
- Analysis of active temperature fluctuations.
Main Results:
- Active fluctuations dominate thermal fluctuations on large length and timescales.
- Multiple crossovers in fluctuation dominance are observed at intermediate scales.
- The framework characterizes fluctuations in active systems.
Conclusions:
- Active fluctuations play a significant role in non-equilibrium systems.
- Local equilibrium can be established at specific length and timescales.
- The study offers insights into the fundamental nature of fluctuations in active matter.
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