Theory and application of Maximum Entropy Production

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Looking at what plants and ecosystems do from a thermodynamic perspective.

Cells, plants and ecosystems – like all open, non-equilibrium systems – import available energy from their environment and export it in more degraded (higher entropy) forms. But at what rate is energy degraded? According to the hypothesis of Maximum Entropy Production (MEP) – as fast as possible. MEP provides a new guiding principle for modelling the flows of energy and matter between plants, ecosystems and their environment, and offers a novel thermodynamic perspective on the origin and evolution of life.

MEP has reproduced key features observed in a diverse range of non-equilibrium systems across physics and biology, from the large-scale distributions of temperature and cloud cover in Earth's climate system to the functional design of the ubiquitous biomolecular motor ATP synthase. But in the absence of a fundamental explanation for MEP, it has remained something of a scientific curiosity.

Our aim is to elucidate the theoretical basis of MEP in order to underpin and guide its wider practical application. We are exploring the idea that MEP can be derived from the fundamental rules of statistical mechanics developed in physics by Boltzmann, Gibbs and Jaynes – implying that MEP is a statistical principle that describes the most likely properties of non-equilibrium systems. Ultimately our goal is to extend the application of MEP from climate modelling – where previous MEP work has mostly focused – to plant and ecosystem modelling.

Further reading

  • Dewar RC. 2010. Maximum entropy production and plant optimization theories. Philosophical Transactions of the Royal Society B (Biological Sciences) 365, 1429-1435. Contribution to Theme Issue (eds. Kleidon A, Cox PM, Mahli Y): Maximum entropy production in ecological and environmental systems: applications and implications.
  • Dewar RC. 2009. Maximum entropy production as an inference algorithm that translates physical assumptions into macroscopic predictions: Don’t shoot the messenger. Entropy 11, 931-944. Contribution to Special Issue (eds. Dyke J, Kleidon A): What is Maximum Entropy Production and how should we apply it?
  • Dewar RC, Juretić, Zupanović P. 2006. The functional design of the rotary enzyme ATP synthase is consistent with maximum entropy production. Chemical Physics Letters 430, 177-182.
  • Dewar RC. 2005. Maximum entropy production and the fluctuation theorem. Journal of Physics A (Mathematical and General) 38, L371-L381.
  • Dewar RC. 2004. Maximum entropy production and non-equilibrium statistical mechanics. In Non-Equilibrium Thermodynamics and Entropy Production : Life, Earth and Beyond (eds. Kleidon A, Lorenz R), Springer-Verlag, pp. 41-55.
  • Dewar RC. 2003. Information theoretic explanation of maximum entropy production, the fluctuation theorem and self-organized criticality in non-equilibrium stationary states. Journal of Physics A (Mathematical and General) 36, 631-641.


Roddy Dewar and Graham Farquhar are researchers in this project, and Roddy also supervises.

We collaborate with an international network of MEP researchers including: Axel Kleidon (Max-Planck Institute for Biogeochemistry, Jena), Peter Cox & Tim Jupp (Exeter University), Amos Maritan (Padua University), Robert Niven (UNSW at ADFA), Hisashi Ozawa (Hiroshima University), Davor Juretić & Pasko Zupanović (Split University).

Updated:  18 August 2019/Responsible Officer:  Director RSB/Page Contact:  Webmaster RSB