Review
Polymer Science
George David Joseph Phillies
Summary: An extensive review of literature simulations of quiescent polymer melts reveals that the Rouse model is invalid in polymer melts. The simulations demonstrate that mean-square amplitudes and time correlation functions of the Rouse mode in polymer melts do not match the predictions of the Rouse model. Additionally, polymer bead displacements in polymer melts are not accurately described by independent Gaussian random processes.
Article
Polymer Science
George David Joseph Phillies
Summary: The Rouse model is the foundation of modern polymer physics, while the Kirkwood-Riseman model is rarely mentioned in current monographs. These models have qualitative differences in terms of the number of internal modes in a polymer molecule. In the Kirkwood-Riseman model, polymers rotate as a whole in a shear field, while in the Rouse model, polymers respond to shear with affine deformation.
Article
Astronomy & Astrophysics
Seray Sahin, Patrick Antolin
Summary: Recent observations have revealed the existence of cool material called coronal rain in addition to the multimillion degree component of the corona. This study investigates the morphological and thermodynamic properties of coronal rain showers and finds a correlation with cooling coronal structures, supporting the thermal nonequilibrium mechanism behind their formation. The study estimates the prevalence and volume of thermal nonequilibrium within the active region, indicating strongly stratified and high-frequency heating.
ASTROPHYSICAL JOURNAL LETTERS
(2022)
Article
Physics, Multidisciplinary
Shane P. Kelly, Ana Maria Rey, Jamir Marino
Summary: The study investigates the far-from-equilibrium dynamics of a many-body spin-boson model, finding that varying the frequency of photons can significantly alter the system's dynamical responses. When photons evolve at a similar rate as spins, they can induce qualitatively distinct frustrated dynamics, illustrating the resilience of glassylike dynamics in the presence of active photonic degrees of freedom. This suggests that disordered quantum many-body systems with resonant photons or phonons can exhibit a rich diagram of nonequilibrium responses, with potential applications in quantum information science in the near future.
PHYSICAL REVIEW LETTERS
(2021)
Article
Chemistry, Physical
Benjamin Lickert, Steffen Wolf, Gerhard Stock
Summary: This study establishes a Markovian Langevin model to reproduce the time evolution of nonstationary data from molecular dynamics simulations, discussing the sampling of free energy landscapes at equilibrium and the association of nonequilibrium processes with biased energy landscapes. The data-driven Langevin equation (dLE) approach is extended to modeling nonequilibrium processes efficiently, correctly accounting for various scenarios such as dissociation of sodium chloride in water, pressure-jump induced nucleation of hard sphere liquid, and sampling of helical peptides from nonstationary short trajectories.
JOURNAL OF PHYSICAL CHEMISTRY B
(2021)
Review
Chemistry, Multidisciplinary
Marcus Muller, Volker Abetz
Summary: This passage discusses the application of porous polymer and copolymer membranes for ultrafiltration and water purification, as well as the formation of isoporous membranes using block copolymers. Understanding the spatiotemporal structure evolution and the interplay of multiple nonequilibrium processes is essential for optimizing membrane performance and fabrication processes.
Article
Biochemistry & Molecular Biology
Charley Schaefer, Peter R. Laity, Chris Holland, Tom C. B. McLeish
Summary: The flow-induced self-assembly of entangled Bombyx mori silk proteins is hypothesized to be aided by the registration of aligned protein chains using intermolecular interacting sticky patches. Despite a clear correlation length of the stickers in the direction of the flow, there is a very broad distribution of protein-chain stretch, suggesting the registration of proteins is not directly coupled to the applied strain but may be a slow statistical process. This qualitative prediction seems to be consistent with the large strains required to induce gelation in rheological measurements under constant shear in the long time scales.
Article
Physics, Fluids & Plasmas
Ashesh Ghosh, Andrew J. Spakowitz
Summary: We present a path-integral formulation that describes the motion of a particle under fluctuating active and thermal forces. This framework predicts the statistical behavior of the particle's stochastic trajectories, taking into account the effect of both Brownian and active forces on any potential landscape. The presence of temporal correlations in the active forces leads to non-Markovian statistics, requiring the inclusion of fixed active-force values at specified times. By specializing our theory to exponentially correlated active forces in a harmonic potential, we obtain exact results for the statistical distributions of the particle's initial position, accounting for the impact of correlated active forces before the initial time. Our theory also allows us to determine the two-point distribution for the active Brownian particle, which governs the joint probability of a particle starting and ending at specified locations. Analysis of the active Brownian statistics reveals that the effect of active forces can be understood in terms of a time-dependent temperature, where its influence depends on the competition between the timescales of active-force correlation and particle relaxation in the harmonic potential. The general results presented in this work are applicable to a wide range of nonequilibrium systems with active and Brownian motion, and the time-dependent temperature serves as a governing principle to describe the interplay between timescales associated with active forces and internal relaxation processes.
Article
Ecology
John P. DeLong, Clayton E. Cressler
Summary: This study evaluates the impact of stochastic processes such as genetic drift on adaptation and finds that stochasticity can alter population dynamics and lead to evolutionary outcomes that are not predicted by classic eco-evolutionary modeling approaches. However, these outcomes are governed by nonequilibrium evolutionary attractors, which are maxima in lifetime reproductive success when stochasticity keeps the ecological system away from the deterministic equilibrium. These NEEAs alter the path of evolution but are not visible through the equilibrium lens of much evolutionary theory. The results reveal the importance of considering population processes during transient periods for a better understanding of the path and pace of evolution.
Article
Physics, Multidisciplinary
R. A. Dumer, M. Godoy
Summary: The nonequilibrium Ising model on a restricted scale-free network has been studied using Monte Carlo simulations. The dynamics of the system are defined by the probability of one- and two-spin flip processes, simulating contact with a heat bath or an external flux of energy. The study found finite critical points and calculated thermodynamic quantities and critical exponents for the system.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2023)
Article
Mechanics
Hongwei Liu, Giovanni Ianniruberto, Giuseppe Marrucci
Summary: This study improves a single-chain model by allowing sticky junctions to move quickly in space without dissociating, leading to better agreement with experimental data. The research also considers a random distribution of stickers and copolymer chemistries, showing good comparison with experimental results.
JOURNAL OF RHEOLOGY
(2022)
Article
Physics, Multidisciplinary
Corneel Casert, Tom Vieijra, Stephen Whitelam, Isaac Tamblyn
Summary: Researchers utilized a neural-network ansatz originally designed for quantum systems to study dynamical large deviations in classical systems, exploring the deviations in model glasses and kinetically constrained models in two dimensions. This study presents the first finite size-scaling analysis of the large-deviation functions of the two-dimensional Fredrickson-Andersen model and investigates the spatial structure of high-activity sectors in the South-or-East model, showcasing the wide applicability of the neural-network state ansatz in physics.
PHYSICAL REVIEW LETTERS
(2021)
Article
Chemistry, Physical
Fabio Caruso
Summary: The coupled nonequilibrium dynamics of electrons and phonons in monolayer MoS2 are studied, with strict phase-space constraints in electron-phonon scattering significantly influencing the decay path of excited electrons and holes. The momentum selectivity in phonon emission results in highly anisotropic population of phonons in reciprocal space, persisting for up to 10 ps until thermal equilibrium is restored by phonon-phonon scattering. Achieving control of the nonequilibrium dynamics of the lattice may offer unexplored opportunities to selectively enhance the phonon population of two-dimensional crystals and tailor electron-phonon interactions over subpicosecond time scales.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Physics, Multidisciplinary
Weilun Yuan, Shuai Yin, Fan Zhong
Summary: The breaking of self-similarity leads to new critical exponents, violating the well-known finite-size scaling or finite-time scaling, and different leading exponents in either the ordered or disordered phases of a model when subjected to nonequilibrium driving. This contrasts sharply with identical exponents and different amplitudes in typical critical phenomena. The results demonstrate the surprising nature of driven nonequilibrium critical phenomena and have potential applications to other classical and quantum phase transitions.
CHINESE PHYSICS LETTERS
(2021)
Article
Physics, Fluids & Plasmas
J. M. Marcos, P. Rodriguez-Lopez, J. J. Melendez, R. Cuerno, J. J. Ruiz-Lorenzo
Summary: This study uses kinetic Monte Carlo simulations to investigate front fluctuations in the spreading of a nonvolatile liquid droplet on a solid substrate. The results show that the diffusion growth of the precursor layer follows a power law with an exponent of 1/2, in agreement with previous studies. The front fluctuations exhibit kinetic roughening properties that depend on temperature, but become temperature independent at higher temperatures. Additionally, evidence of intrinsic anomalous scaling is found, with different roughness exponents at different length scales.
