Informatic versus Thermodynamic Entropy Production in Active Systems скачать в хорошем качестве

Informatic versus Thermodynamic Entropy Production in Active Systems

Abstract: Stochastic thermodynamics connects the steady-state entropy production rate (EPR) of a system connected to a heat bath with the log ratio of probabilities of forward and time-reversed trajectories. Extending the resulting formula to coarse-grained models of systems much further from equilibrium, such as schools of fish or herds of wildebeest, results in an informatic EPR (IEPR) that depends only on order parameter dynamics and is no longer is connected with microscopic heat flow, but remains a valuable quantifier of macroscopic irreversibility. When the same coarse-grained models describe more microscopic processes (such as active phase separation within a biological cell), a connection to heat flow should be recoverable. To achieve this we can embed the coarse-grained model into a larger model involving explicit (if schematic) chemical reactions such that the whole system is governed by linear irreversible thermodynamics. All the active terms in the order parameter dynamics then become off-diagonal elements of an Onsager matrix whose symmetry determines the remaining chemical couplings and thus the full heat production. This exceeds the IEPR by a term that contains complementary spatial information to the IEPR itself. About the speaker: Prof Mike Cates completed a PhD under Sir Sam Edwards in the Cavendish Laboratory, Cambridge and, after postdocs in the USA, joined the faculty there in 1989. In 1995 he took up the Chair of Natural Philosophy at the University of Edinburgh, which he held for 20 years before returning to Cambridge, where he is the 19th Lucasian Professor of Mathematics and a Royal Society Research Professor in the Department of Applied Mathematics and Theoretical Physics. He was elected a Fellow of the Royal Society in 2007 and became an International Member of the US National Academy of Sciences in 2021. For many years his work has addressed the nonequilibrium statistical mechanics of soft matter systems driven by flow, including polymers, colloids and granular materials. For these contributions he has received the Gold Medal, the Weissenberg Award, and the Bingham Medal of the UK, European and US Societies of Rheology respectively. Since 2008 he has also worked on active matter systems in which nonequilibrium is maintained instead by self-propulsion or similar driving at the scale of the system's local constituents. He is one of the originators of the theory of motility-induced phase separation (MIPS) and has recently focused on developing and studying field theories for active systems.