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Measuring Entropy with Tactile Geometry: A Physical Surface Framework for Complex Systems
William Faulkner
Posted: 10 April 2025
Analytical Representations of Thermodynamic Functions of Thomas-Fermi Model
S. V. G. Menon
Posted: 02 April 2025
Maxwell's Demon Is Foiled by the Entropy Cost of Measurement, Not Erasure
Ruth Kastner
Posted: 27 March 2025
The Total Entropic Quantity Framework: A Conceptual Foundation for Entropy, Time, and Physical Evolution
David Sigtermans
Posted: 26 March 2025
Dynamic Balance: A Thermodynamic Principle for the Emergence of the Golden Ratio in Open Non-Equilibrium Steady States
Alejandro Ruiz
Posted: 24 March 2025
The Significance of the Entropic Measure of Time in Natural Sciences
Leonid M Martyushev
Posted: 21 March 2025
Tunneling, the Equilibrium Constant, and Epicatalysis: A Second-Law Paradox?
Jack Denur
Consider one particle (which could be an atom, molecule, Brownian particle, etc.) in thermodynamic equilibrium with a heat reservoir at temperature T. This particle can be in a low-potential-energy well L whose energy floor is EL and whose degeneracy is GL or in a higher (or at least equally high) potential-energy well H whose energy floor is EH and whose degeneracy is GH. L and H are separated by a barrier B, which the particle can traverse. The Second Law of Thermodynamics asserts that the ratio of the probability of this particle being in H to that of it being in L, i.e., the equilibrium constant Keq corresponding to its dissemination between the two wells L and H, is in accordance with the Boltzmann (or canonical) distribution: Keq = (GH/GL)exp[−(EH – EL)/kT]. Given thermodynamic equilibrium this indeed always obtains if transits between L and H occur only via thermal excitation of our particle. But we show that despite thermodynamic equilibrium this does not obtain if transits between L and H occur both via thermal excitation and via tunneling. Implications concerning the Second Law of Thermodynamics are discussed. Next, we provide general remarks pertaining to catalysis versus epicatalysis. Then we spotlight that only one aspect of the Second Law can challenged: the aspect thereof that precludes a net decrease in entropy. Following concluding remarks, the minimum work that the Second Law requires to change Keq is evaluated in the Appendix.
Consider one particle (which could be an atom, molecule, Brownian particle, etc.) in thermodynamic equilibrium with a heat reservoir at temperature T. This particle can be in a low-potential-energy well L whose energy floor is EL and whose degeneracy is GL or in a higher (or at least equally high) potential-energy well H whose energy floor is EH and whose degeneracy is GH. L and H are separated by a barrier B, which the particle can traverse. The Second Law of Thermodynamics asserts that the ratio of the probability of this particle being in H to that of it being in L, i.e., the equilibrium constant Keq corresponding to its dissemination between the two wells L and H, is in accordance with the Boltzmann (or canonical) distribution: Keq = (GH/GL)exp[−(EH – EL)/kT]. Given thermodynamic equilibrium this indeed always obtains if transits between L and H occur only via thermal excitation of our particle. But we show that despite thermodynamic equilibrium this does not obtain if transits between L and H occur both via thermal excitation and via tunneling. Implications concerning the Second Law of Thermodynamics are discussed. Next, we provide general remarks pertaining to catalysis versus epicatalysis. Then we spotlight that only one aspect of the Second Law can challenged: the aspect thereof that precludes a net decrease in entropy. Following concluding remarks, the minimum work that the Second Law requires to change Keq is evaluated in the Appendix.
Posted: 14 March 2025
Multi-Particle-Collision Simulation of Heat Transfer in Low-Dimensional Fluids
Rongxiang Luo,
Stefano Lepri
Posted: 14 March 2025
Tunneling, the Equilibrium Constant, and Epicatalysis: A Second-Law Paradox?
Jack Denur
Posted: 03 March 2025
Local-Equilibrium Approximation in Non-Equilibrium Thermodynamics of Diffusion
Kim R. Kristiansen,
Bjørn Hafskjold
The local equilibrium approximation (LEA) is a central assumption in many applications of non-equilibrium thermodynamics involving the transport of energy, mass, and momentum. However, assessing the validity of the LEA remains challenging due to the limited development of tools for characterizing non-equilibrium states compared to equilibrium states. To address this, we have developed a theory based on kinetic theory, which provides a nonlinear extension of the telegrapher’s equation commonly discussed in non-equilibrium frameworks that extend beyond the LEA. A key result of this theory is a steady-state diffusion equation that accounts for the constraint imposed by available thermal energy on the diffusion flux. The theory is suitable for analysis of steady-state composition profiles and can be used to quantify the deviation from local equilibrium. To validate the theory, we performed molecular dynamics simulations. The results show that deviation from local equilibrium can be systematically quantified, and for the diffusion process we have studied here, we have confirmed that the LEA remains accurate even under extreme concentration gradients in gas mixtures.
The local equilibrium approximation (LEA) is a central assumption in many applications of non-equilibrium thermodynamics involving the transport of energy, mass, and momentum. However, assessing the validity of the LEA remains challenging due to the limited development of tools for characterizing non-equilibrium states compared to equilibrium states. To address this, we have developed a theory based on kinetic theory, which provides a nonlinear extension of the telegrapher’s equation commonly discussed in non-equilibrium frameworks that extend beyond the LEA. A key result of this theory is a steady-state diffusion equation that accounts for the constraint imposed by available thermal energy on the diffusion flux. The theory is suitable for analysis of steady-state composition profiles and can be used to quantify the deviation from local equilibrium. To validate the theory, we performed molecular dynamics simulations. The results show that deviation from local equilibrium can be systematically quantified, and for the diffusion process we have studied here, we have confirmed that the LEA remains accurate even under extreme concentration gradients in gas mixtures.
Posted: 14 February 2025
Chaotic Interaction Between Thermodynamic Systems
Ekrem Aydiner
In the previous work \cite{Aydiner_2024}, we presented a new interaction scheme that describes the interaction of thermodynamic systems. Using this interaction scheme, we showed that the interaction of dark matter and dark energy is chaotic. We also predicted that the results could be generalized to all particle and thermodynamic systems. In addition, we gave physical definitions of the concepts of chaos and self-organization. More importantly, we proposed a new law of physics based on interacting systems. Then, in this study, we considered two thermodynamic systems interacting under different conditions to prove the universality of the physical law we propose. We showed that these systems also have chaotic interaction dynamics. Furthermore, we discussed the physical and philosophical foundations of this new physics law and definition of chaos. In addition, we introduced a new action principle and a new complexity definition.
In the previous work \cite{Aydiner_2024}, we presented a new interaction scheme that describes the interaction of thermodynamic systems. Using this interaction scheme, we showed that the interaction of dark matter and dark energy is chaotic. We also predicted that the results could be generalized to all particle and thermodynamic systems. In addition, we gave physical definitions of the concepts of chaos and self-organization. More importantly, we proposed a new law of physics based on interacting systems. Then, in this study, we considered two thermodynamic systems interacting under different conditions to prove the universality of the physical law we propose. We showed that these systems also have chaotic interaction dynamics. Furthermore, we discussed the physical and philosophical foundations of this new physics law and definition of chaos. In addition, we introduced a new action principle and a new complexity definition.
Posted: 22 January 2025
Extremal Principles of Thermodynamics in an Exactly Solvable Rayleigh Gas Model
Pulat Aripovich Tadjibaev,
Diyor Pulatovich Tadjibaev
Posted: 21 January 2025
Analysis of Methods for Intensifying Heat and Mass Transfer in Liquid Media
Anatoliy Pavlenko
Posted: 15 January 2025
A Metric for the Entropic Purpose of a System
Michael C. Parker,
Chris Jeynes,
Stuart D. Walker
Purpose in systems is considered to be beyond the purview of science, since it is thought to be intrinsically personal. However, just as Claude Shannon was able to define an impersonal measure of information, so we formally define the (impersonal) ‘entropic purpose’ of an information system (using the theoretical apparatus of Quantitative Geometrical Thermodynamics) as the line integral of an entropic “purposive” Lagrangian defined in hyperbolic space across the complex temporal plane. We verify that this Lagrangian is well-formed: it has the appropriate variational (Euler-Lagrange) behaviour. We also discuss the teleological characteristics of such variational behaviour (featuring both thermodynamically reversible and irreversible temporal measures), so that a “Principle of Least (entropic) Purpose” can be adduced for any information-producing system. We show that entropic purpose is (approximately) identified with the information created by the system: an empirically measurable quantity. Exploiting the relationship between the entropy production of a system and its energy Hamiltonian, we also show how Landauer’s principle also applies to the creation of information; any purposive system that creates information will also dissipate energy. Finally, we discuss how ‘entropic purpose’ might be applied in artificial intelligence contexts (where degrees of system ‘aliveness’ need to be assessed), and in cybersecurity (where this metric for ‘entropic purpose’ might be exploited to help distinguish between people and bots).
Purpose in systems is considered to be beyond the purview of science, since it is thought to be intrinsically personal. However, just as Claude Shannon was able to define an impersonal measure of information, so we formally define the (impersonal) ‘entropic purpose’ of an information system (using the theoretical apparatus of Quantitative Geometrical Thermodynamics) as the line integral of an entropic “purposive” Lagrangian defined in hyperbolic space across the complex temporal plane. We verify that this Lagrangian is well-formed: it has the appropriate variational (Euler-Lagrange) behaviour. We also discuss the teleological characteristics of such variational behaviour (featuring both thermodynamically reversible and irreversible temporal measures), so that a “Principle of Least (entropic) Purpose” can be adduced for any information-producing system. We show that entropic purpose is (approximately) identified with the information created by the system: an empirically measurable quantity. Exploiting the relationship between the entropy production of a system and its energy Hamiltonian, we also show how Landauer’s principle also applies to the creation of information; any purposive system that creates information will also dissipate energy. Finally, we discuss how ‘entropic purpose’ might be applied in artificial intelligence contexts (where degrees of system ‘aliveness’ need to be assessed), and in cybersecurity (where this metric for ‘entropic purpose’ might be exploited to help distinguish between people and bots).
Posted: 14 January 2025
Entropy in the Context of Gravitational Repulsion Opens New Avenues for Theoretical Exploration
Chithra Kirthi Gamini Piyadasa
Posted: 03 January 2025
State-Space Curvatures and Self-Organizing Criticalities
Martijn Veening
Self-organizing criticalities are a much studied notion, within disciplines ranging from ecosystems/living systems to economic systems and markets. But there is still no consensus or general framework for explaining the ’spontaneous’ emergence of this kind of ’orderly’ behavior. This paper generalizes the second law of thermodynamics to dynamic state-spaces with increasing dimensionality and introduces the notion of spate-space curvature, in order to provide such a framework.
Self-organizing criticalities are a much studied notion, within disciplines ranging from ecosystems/living systems to economic systems and markets. But there is still no consensus or general framework for explaining the ’spontaneous’ emergence of this kind of ’orderly’ behavior. This paper generalizes the second law of thermodynamics to dynamic state-spaces with increasing dimensionality and introduces the notion of spate-space curvature, in order to provide such a framework.
Posted: 24 December 2024
Thermodynamic Theory of Gravity and Buoyancy
Fei Wang,
Britta Nestler
Posted: 23 December 2024
Entropy Production in an Electro-Membrane Process at Underlimiting Currents. Influence of Temperature
Juan Carlos Maroto,
Sagrario Muñoz,
V. María Barragán
Posted: 11 December 2024
Revisions of the Phenomenological and Statistical Statements of the Second Law of Thermodynamics
Grzegorz Marcin Koczan,
Roberto Zivieri
Posted: 14 November 2024
A New General Correlation for the Influence Parameter in Density Gradient Theory and Peng-Robinson Equation of State for N-Alkanes
Isidro Cachadiña,
Ariel Hernández,
Ángel Mulero
Posted: 29 October 2024
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