Recurrent, nonequilibrium systems and the Markov blanket assumption

Markov blankets –statistical independences between system and environment– have become popular to describe the boundaries of living systems under Bayesian views of cognition. The intuition behind Markov blanket originates from considering acyclic, atemporal networks. In contrast, living systems display recurrent interactions that generate pervasive couplings between system and environment, making Markov blankets highly unusual and restricted to particular cases.

Nonequilibrium Time Reversibility with Maps and Walks

Time-reversible dynamical simulations of nonequilibrium systems exemplify both Loschmidt’s and Zermélo’s paradoxes. That is, computational time-reversible simulations invariably produce solutions consistent with the irreversible Second Law of Thermodynamics (Loschmidt’s) as well as periodic in the time (Zermélo’s, illustrating Poincaré recurrence). Understanding these paradoxical aspects of time-reversible systems is enhanced here by studying the simplest pair of such model systems. The first is time-reversible, but nevertheless dissipative and periodic, the piecewise-linear compressible Baker Map. The fractal properties of that two-dimensional map are mirrored by an even simpler example, the one-dimensional random walk, confined to the unit interval. As a further puzzle the two models yield ambiguities in determining the fractals’ information dimensions. These puzzles, including the classical paradoxes, are reviewed and explored here.

Investigating the characteristics of the development of the boundary layer motion of locally nonequilibrium systems

The method of integral momentum transfer relations has been extended to polymer systems with a locally nonequilibrium relaxation microstructure. The influence of the locally non-equilibrium transfer of the impulse flux on the characteristics of the development of their boundary-layer motion is analyzed.

Overview of the III International Conference on Applied Physics, Information Technologies and Engineering – APITECH-III 2021

The overview describes the main directions and results of the III International Conference APITECH-III 2021 held in Krasnoyarsk from September 24 to October 3, 2021. It gives the details about the participants and the proceedings. The purpose of the Conference is to share the experience of leading experts in the application of modern methods of applied physics and information technology in high-tech production, in the fields of aerospace, energy, chemical and oil and gas engineering, as well as in modern areas of neuroinformatics and modeling of nonequilibrium systems. The JSC “ISS-Reshetnev Company” and Siberian Scientific Centre DNIT sponsored the Conference.

Algorithms for monitoring the functioning of nonequilibrium information processing systems

The authors have developed an algorithm for monitoring the functioning of nonequilibrium systems, which is based on such operations as establishing the range for permissible values of efficiency probabilities of structural elements functioning, establishing permissible values of structural elements amount, plotting the system entropy dependence on structural elements amount and their effectiveness probability, constructing phase space of the system functioning and determination of the boundaries of regions with nonequilibrium stability. Practical testing of the developed algorithm for monitoring the functioning of nonequilibrium systems has shown that this algorithm can be used to solve several practical problems related to functioning monitoring and predicting the state of a wide variety of nonequilibrium systems.

Unifying fluctuation-dissipation temperatures of slow-evolving nonequilibrium systems from the perspective of inherent structures

For nonequilibrium systems, how to define temperature is one of the key and difficult issues to solve. Although effective temperatures have been proposed and studied to this end, it still remains elusive what they actually are. Here, we focus on the fluctuation-dissipation temperatures and report that such effective temperatures of slow-evolving systems represent characteristic temperatures of their equilibrium counterparts. By calculating the fluctuation-dissipation relation of inherent structures, we obtain a temperature-like quantity TIS. For monocomponent crystal-formers, TIS agrees well with the crystallization temperature Tc, while it matches with the onset temperature Ton for glass-formers. It also agrees with effective temperatures of typical nonequilibrium systems, such as aging glasses, quasi-static shear flows, and quasi-static self-propelled flows. From the unique perspective of inherent structures, our study reveals the nature of effective temperatures and the underlying connections between nonequilibrium and equilibrium systems and confirms the equivalence between Ton and Tc.