BEGIN:VCALENDAR VERSION:2.0 PRODID:-//jEvents 2.0 for Joomla//EN CALSCALE:GREGORIAN METHOD:PUBLISH BEGIN:VTIMEZONE TZID:America/New_York BEGIN:STANDARD DTSTART:20210125T104500 RDATE:20210314T030000 TZOFFSETFROM:-0400 TZOFFSETTO:-0500 TZNAME:America/New_York EST END:STANDARD BEGIN:STANDARD DTSTART:20211107T010000 RDATE:20220313T030000 TZOFFSETFROM:-0400 TZOFFSETTO:-0500 TZNAME:America/New_York EST END:STANDARD BEGIN:STANDARD DTSTART:20221106T010000 RDATE:20230312T030000 TZOFFSETFROM:-0400 TZOFFSETTO:-0500 TZNAME:America/New_York EST END:STANDARD BEGIN:STANDARD DTSTART:20231105T010000 RDATE:20240310T030000 TZOFFSETFROM:-0400 TZOFFSETTO:-0500 TZNAME:America/New_York EST END:STANDARD BEGIN:STANDARD DTSTART:20241103T010000 RDATE:20250309T030000 TZOFFSETFROM:-0400 TZOFFSETTO:-0500 TZNAME:America/New_York EST END:STANDARD BEGIN:STANDARD DTSTART:20251102T010000 RDATE:20260308T030000 TZOFFSETFROM:-0400 TZOFFSETTO:-0500 TZNAME:America/New_York EST END:STANDARD BEGIN:STANDARD DTSTART:20261101T010000 RDATE:20270314T030000 TZOFFSETFROM:-0400 TZOFFSETTO:-0500 TZNAME:America/New_York EST END:STANDARD BEGIN:STANDARD DTSTART:20271107T010000 RDATE:20280312T030000 TZOFFSETFROM:-0400 TZOFFSETTO:-0500 TZNAME:America/New_York EST END:STANDARD BEGIN:STANDARD DTSTART:20281105T010000 RDATE:20290311T030000 TZOFFSETFROM:-0400 TZOFFSETTO:-0500 TZNAME:America/New_York EST END:STANDARD BEGIN:DAYLIGHT DTSTART:20210314T030000 RDATE:20211107T010000 TZOFFSETFROM:-0500 TZOFFSETTO:-0400 TZNAME:America/New_York EDT END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20220313T030000 RDATE:20221106T010000 TZOFFSETFROM:-0500 TZOFFSETTO:-0400 TZNAME:America/New_York EDT END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20230312T030000 RDATE:20231105T010000 TZOFFSETFROM:-0500 TZOFFSETTO:-0400 TZNAME:America/New_York EDT END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20240310T030000 RDATE:20241103T010000 TZOFFSETFROM:-0500 TZOFFSETTO:-0400 TZNAME:America/New_York EDT END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20250309T030000 RDATE:20251102T010000 TZOFFSETFROM:-0500 TZOFFSETTO:-0400 TZNAME:America/New_York EDT END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20260308T030000 RDATE:20261101T010000 TZOFFSETFROM:-0500 TZOFFSETTO:-0400 TZNAME:America/New_York EDT END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20270314T030000 RDATE:20271107T010000 TZOFFSETFROM:-0500 TZOFFSETTO:-0400 TZNAME:America/New_York EDT END:DAYLIGHT BEGIN:DAYLIGHT DTSTART:20280312T030000 RDATE:20281105T010000 TZOFFSETFROM:-0500 TZOFFSETTO:-0400 TZNAME:America/New_York EDT END:DAYLIGHT END:VTIMEZONE BEGIN:VEVENT UID:05ad2434a68a1b6be425a9bee21cf2f9 CATEGORIES:Mathematical Physics Seminar CREATED:20220110T132047 SUMMARY:Informatic and Thermodynamic Entropy Production in Active Systems LOCATION:Zoom DESCRIPTION:Abstract: For a near-equilibrium system connected to a heat bath, there is a fundamental relationship between the steady-state entropy production rate (EPR) and the log of the ratio of probabilities of forward and time revers ed trajectories. I will illustrate this first in the context of a single pa rticle, and then explain how the result generalizes, in principle, to coars e-grained models of active matter, described by field theories. In practice , however, these theories often address systems extremely FAR from equilibr ium, such as schools of fish or herds of wildebeest, for which the connecti on between macroscopic dynamics and microscopic heat flow is tenuous (at be st). \nIn these cases we can nonetheless calculate an informatic counterpar t of EPR that depends only on the coarse-grained dynamics and turns out to be a very useful quantifier of macroscopic irreversibility. In other situat ions, the same coarse-grained models are used to describe processes that ar e relatively microscopic and not so far from equilibrium, such as phase sep aration within a biological cell. Here a connection to heat flow should rem ain intact. I will show how to identify it by embedding the coarse-grained model into a larger model with explicit chemical reactions and heat flows, such that the whole system is governed by linear irreversible thermodynamic s. All the active terms in the order parameter dynamics then become off-dia gonal elements of an Onsager matrix whose symmetry determines the remaining chemical couplings and thus the full heat production.\n X-ALT-DESC;FMTTYPE=text/html:

Abstract: For a near-equilibrium system connected to a heat bath, there is a fundamental relationship between the steady-state entropy production r ate (EPR) and the log of the ratio of probabilities of forward and time rev ersed trajectories. I will illustrate this first in the context of a single particle, and then explain how the result generalizes, in principle, to co arse-grained models of active matter, described by field theories. In pract ice, however, these theories often address systems extremely FAR from equil ibrium, such as schools of fish or herds of wildebeest, for which the conne ction between macroscopic dynamics and microscopic heat flow is tenuous (at best).
In these cases we can nonetheless calculate an informatic cou nterpart of EPR that depends only on the coarse-grained dynamics and turns out to be a very useful quantifier of macroscopic irreversibility. In other situations, the same coarse-grained models are used to describe processes that are relatively microscopic and not so far from equilibrium, such as ph ase separation within a biological cell. Here a connection to heat flow sho uld remain intact. I will show how to identify it by embedding the coarse-g rained model into a larger model with explicit chemical reactions and heat flows, such that the whole system is governed by linear irreversible thermo dynamics. All the active terms in the order parameter dynamics then become off-diagonal elements of an Onsager matrix whose symmetry determines the re maining chemical couplings and thus the full heat production.

CONTACT:Michael Cates - University of Cambridge DTSTAMP:20260828T104809 DTSTART;TZID=America/New_York:20220126T104500 DTEND;TZID=America/New_York:20220126T114500 SEQUENCE:0 TRANSP:OPAQUE END:VEVENT END:VCALENDAR