Milestoning estimators of dissipation in systems observed at a coarse resolution

Proceedings of the National Academy of Sciences, Год журнала: 2024, Номер 121(17)

Опубликована: Апрель 16, 2024

Many nonequilibrium, active processes are observed at a coarse-grained level, where different microscopic configurations projected onto the same observable state. Such “lumped” observables display memory, and in many cases, irreversible character of underlying dynamics becomes blurred, e.g., when projection hides dissipative cycles. As result, observations appear less irreversible, it is very challenging to infer degree broken time-reversal symmetry. Here we show, contrary intuition, that by ignoring parts already state space may—via process called milestoning—improve entropy-production estimates. We present diverse examples milestoning systematically renders “closer dynamics” thereby improves thermodynamic inference from lumped data assuming given range hypothesize this effect quite general. Moreover, whereas correct general physical definition time reversal presence memory remains unknown, here show means physically relevant least for semi-Markov first second order, waiting-time contributions arising adopting naive Markovian generally must be discarded.

Язык: Английский

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Thermodynamic cost for precision of general counting observables

Physical review. E, Год журнала: 2024, Номер 109(6)

Опубликована: Июнь 11, 2024

We analytically derive universal bounds that describe the tradeoff between thermodynamic cost and precision in a sequence of events related to some internal changes an otherwise hidden physical system. The is quantified by fluctuations either number counted over time or waiting times successive events. Our results are valid for same broad class nonequilibrium driven systems considered uncertainty relation, but they extend both time-symmetric asymmetric observables. show how optimal saturating can be achieved. For waiting-time observables, phase transition configuration arises, where higher achieved combining several signals.

Язык: Английский

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Fluctuating entropy production on the coarse-grained level: Inference and localization of irreversibility

Physical Review Research, Год журнала: 2024, Номер 6(2)

Опубликована: Май 16, 2024

Stochastic thermodynamics provides the framework to analyze thermodynamic laws and quantities along individual trajectories of small but fully observable systems. If level fails capture all relevant degrees freedom, some form effective, coarse-grained dynamics naturally emerges for which principles stochastic generally cease be applicable straightforwardly. Our work unifies notion entropy production an trajectory with that a by establishing based on snippets Markovian events as fundamental building blocks. A key asset trajectory-based fluctuating is ability localize contributions total in time space. As illustration potential application inference we introduce method detection hidden driving. The applies equally even odd variables and, therefore, includes peculiar case underdamped Langevin dynamics. Published American Physical Society 2024

Язык: Английский

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Entropy, irreversibility and inference at the foundations of statistical physics

Nature Reviews Physics, Год журнала: 2024, Номер 6(6), С. 382 - 393

Опубликована: Май 1, 2024

Язык: Английский

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Dynamics of Microscale and Nanoscale Systems in the Weak-Memory Regime

Physical Review Letters, Год журнала: 2025, Номер 134(3)

Опубликована: Янв. 21, 2025

Memory effects are ubiquitous in small-scale systems. They emerge from interactions between accessible and inaccessible degrees of freedom give rise to evolution equations that nonlocal time. If the characteristic timescales sharply separated, locality can be restored through standard Markov approximation. Here, we show this approach rigorously extended a well-defined weak-memory regime, where relevant comparable order magnitude. We derive explicit bounds on error local approximation convergent perturbation scheme for its construction. Being applicable any time equation is autonomous linear variables interest, our theory provides unifying framework systematic description memory effects. Published by American Physical Society 2025

Язык: Английский

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Dynamics of microscale and nanoscale systems in the weak-memory regime: A mathematical framework beyond the Markov approximation

Physical review. E, Год журнала: 2025, Номер 111(1)

Опубликована: Янв. 21, 2025

The visible dynamics of small-scale systems are strongly affected by unobservable degrees freedom, which can belong to either external environments or internal subsystems and almost inevitably induce memory effects. Formally, such inaccessible freedom be systematically eliminated from essentially any microscopic model through projection operator techniques, result in nonlocal time evolution equations. This article investigates how under what conditions locality rigorously restored beyond the standard Markov approximation, generally requires characteristic timescales accessible sharply separated. Specifically, we consider equations that autonomous linear variables interest. For this class models, prove a mathematical theorem establishes well-defined weak-memory regime, where faithful local approximations exist, even if relevant comparable order magnitude. generators these approximations, become exact long-time limit, independent determined arbitrary accuracy convergent perturbation theory strength, generator is recovered first order. illustration, work out three simple, yet instructive, examples covering coarse-grained jump networks, semi-Markov processes, generalized Langevin Published American Physical Society 2025

Язык: Английский

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Evidence and quantification of memory effects in competitive first-passage events

Science Advances, Год журнала: 2025, Номер 11(12)

Опубликована: Март 21, 2025

Splitting probabilities quantify the likelihood of a given outcome out competitive events. This key observable random walk theory, historically introduced as gambler’s ruin problem, is well understood for memoryless (Markovian) processes. However, in complex systems such polymer fluids, motion particle should typically be described process with memory, which splitting are much less characterized analytically. Here, we introduce an analytical approach that provides one-dimensional isotropic non-Markovian Gaussian processes stationary increments, case two targets. analysis shows controlled by out-of-equilibrium trajectories observed after first passage. directly evidenced prototypical experimental reaction scheme viscoelastic fluids. These results extended to d -dimensional large confining volumes, opening path toward study events media.

Язык: Английский

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Universal bounds on entropy production inferred from observed statistics

Physical Review Research, Год журнала: 2023, Номер 5(4)

Опубликована: Дек. 15, 2023

Nonequilibrium processes break time-reversal symmetry and generate entropy. Living systems are driven out-of-equilibrium at the microscopic level of molecular motors that exploit chemical potential gradients to transduce free energy mechanical work, while dissipating energy. The amount dissipation, or entropy production rate (EPR), sets thermodynamic constraints on cellular processes. Practically, calculating total EPR in experimental is challenging due limited spatiotemporal resolution lack complete information every degree freedom. Here, we propose an inference approach for a tight lower bound given partial information, based optimization scheme uses observed transitions waiting times statistics. We introduce hierarchical bounds relying first- second-order transitions, moments time distributions, apply our two generic hidden network motor, with lumped states. Finally, show can be obtained even when assuming simpler topology full system.

Язык: Английский

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General theory for localizing the where and when of entropy production meets single-molecule experiments

Proceedings of the National Academy of Sciences, Год журнала: 2024, Номер 121(33)

Опубликована: Авг. 9, 2024

The laws of thermodynamics apply to biophysical systems on the nanoscale as described by framework stochastic thermodynamics. This theory provides universal, exact relations for quantities like work, which have been verified in experiments where a fully resolved description allows direct access such quantities. Complementary studies consider partially hidden, coarse-grained descriptions, mean entropy production typically is not directly accessible but can be bounded terms observable Going beyond mean, we introduce fluctuating that applies individual trajectories under time-dependent driving. Thus, this concept applicable broad and experimentally significant class driven all relevant states resolved. We provide paradigmatic example studying an protein unfolding process. As consequence, entire distribution rather than merely its retains spatial temporal information about microscopic In particular, obtain bound physical events.

Язык: Английский

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Emergence of Memory in Equilibrium versus Nonequilibrium Systems

Physical Review Letters, Год журнала: 2024, Номер 132(14)

Опубликована: Апрель 2, 2024

Experiments often probe observables that correspond to low-dimensional projections of high-dimensional dynamics. In such situations distinct microscopic configurations become lumped into the same observable state. It is well known correlations between and hidden degrees freedom give rise memory effects. However, how under which conditions these emerge remain poorly understood. Here we shed light on two fundamentally different scenarios emergence in minimal stationary systems, where observed either evolve cooperatively or are coupled by a nonequilibrium current. reversible setting strongest manifests when timescales dynamics overlap, whereas, strikingly, driven maximal emerges clear timescale separation. Our results hint at possibility fundamental differences way equilibrium versus systems may be utilized as “diagnostic” underlying transport mechanism. Published American Physical Society 2024

Язык: Английский

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