IAS-Research Seminar by Alejandro Merlo (EHU/UPV), “Life and thermodynamics: the contribution of Earth system science”

To participate, please contact: alejandra.mtz.quintero@gmail.com

 

Bio: Alejandro Merlo Ote (EHU/UPV)

Abstract: The classic thermodynamic account of life describes organisms as open systems, which compensate their internal low entropy by an increased dissipation in their surroundings. An intuitive consequence of this account is that complex living systems would seem to necessarily decrease the potential for life in their environment by their increased entropy production.

Within this framework, some accounts have attempted to explain biological organisation as a manifestation of the second law and the tendency to increase entropy; others have rejected this position as reductionist and moved to an account of biological organisation in non-thermodynamic terms. However, even if thermodynamics cannnot give a full account of biological organisation, there is in all cases a thermodynamic background to biological phenomena which needs to be accounted for in an understanding of the materiality of life.

In this context, James Lovelock’s idea, according to which a planet with life could be distinguished because of a thermodynamic disequilibrium in its atmospheric composition, shifts the discussion to the planetary scale, where the presence of Life becomes the explanans of a certain thermodynamic configuration. This observation, which corresponds to the Gaïan principle according to which Life modifies its physical environment to improve and maintain its own conditions of existence, has been recently developed in a systematic way by German physicist Axel Kleidon.

From this planetary standpoint, it is Life together with its physical environment that has to be considered as the primordial open, far from equilibrium dissipative system. So, while individual organisms or complex organisations within the Earth can be described as dissipative systems if considered separately from the whole, a full thermodynamic account needs to integrate them in the planetary scale, where they might (or might not) function as part of the global material organisation that sustains a low entropy environment.