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Improved bounds on entropy production in living systems
Dominic J Skinner1, Jörn Dunkel2
1Department of Mathematics, Massachusetts Institute of Technology, Cambridge, MA 02139.
Summary
Living systems defy the second law of thermodynamics by consuming energy to create order, increasing environmental entropy. This study introduces an improved method to estimate entropy production rates from partial biological data.
Area of Science:
- Thermodynamics
- Biophysics
- Cellular Biology
Background:
- Living systems locally decrease entropy by consuming free energy, increasing environmental entropy.
- Estimating entropy production rates is crucial for understanding cellular process efficiency.
- Existing methods struggle with systems where many degrees of freedom are unobserved.
Purpose of the Study:
- To develop an improved method for estimating entropy production rates in biological systems using partial measurements.
- To provide provably optimal estimates under specific measurable transition statistics.
- To reveal nonzero entropy production in systems that appear time-symmetric.
Main Methods:
- Reformulating entropy production estimation within an optimization framework.
- Inferring improved bounds on entropy production from partial system measurements.
- Utilizing measurable transition statistics for optimal estimation.
Main Results:
- Developed an improved estimator for entropy production rates from partial biological data.
- Demonstrated that the new method can detect entropy production in time-symmetric nonequilibrium processes.
- Achieved provably optimal estimates under defined measurement conditions.
Conclusions:
- The novel optimization framework offers a more robust way to quantify entropy production in complex biological systems.
- This approach enhances our understanding of energy consumption and thermodynamic efficiency in life.
- Applicable to diverse biological systems, including molecular motors and cellular oscillations.
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