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Publication: Entropy defect - Algebra and thermodynamics
Nov. 22, 2023

We investigate the way the entropy of a system can be partitioned into the entropies of its constituents in consistency with thermodynamics. This partitioning is described through the concept of an entropy defect, which measures the missing entropy between the sum of entropies of a system's constituents and the entropy of the combined system;…

Publication: Connection between Heating and Polytropes
Oct. 12, 2023

The paper derives the one-to-one connecting relationships between plasma heating and its polytropic index, and addresses the consequences through the transport equation of temperature. Thermodynamic polytropic processes are classified in accordance to their polytropic index, the exponent of the power-law relationship of thermal pressure…

Publication: Estimates of Proton and Electron Heating Rates Extended to the Near-Sun Environment
Sept. 27, 2023

The differential heating of charged species due to dissipation of turbulent fluctuations plays a key role in solar wind evolution. Measurements from previous heliophysics missions have provided estimates of proton and electron heating rates beyond 0.27 au. Using Parker Solar Probe (PSP) data accumulated during the first 10 encounters, we extend…

Publication: Extensive Entropy - the case of Zero Entropy Defect
Sept. 26, 2023

This paper shows that the Rényi and Boltzmann-Gibbs (BG) extensive entropies share the same functional relationship with the nonextensive entropy associated with kappa distributions, which coincides with the well-known Havrda/Charvát/Daróczy/Tsallis (HCDT) entropy. We find that while the relationship between kappa/HCDT and Rényi entropies is…

Publication: Transport equation of kappa distributions in the heliosphere
Aug. 23, 2023

In this paper we develop the transport equation of kappa, the fundamental thermodynamic parameter that labels kappa distributions of particle velocities. Using the recently developed concept of entropy defect, we are able to formulate the transport equation of kappa as a function of a general positive or negative rate of entropy change. Then,…

Publication: Collisional-like dissipation in collisionless plasmas
Aug. 16, 2023

When collisions are strong in a magnetized plasma, standard closures provide simple representations of dissipation in terms of coefficients of viscosity and resistivity. In the opposite limit of weak collisions, the analogous physical effects that lead to dissipation are present, but the simple approximations to describe them, the closures, are…

Publication: Temperature of the Polar Inner Heliosheath - Connection to Solar Activity
June 29, 2023

We study the thermodynamics of the plasma protons in the polar regions of the inner heliosheath (IHS) and its connection with solar activity over solar cycle 24. First, we express the thermodynamic parameters of this plasma with respect to the year of energetic neutral atom (ENA) creation and perform a statistical analysis of temperatures, in…

Publication: Formation, Structure, and Detectability of the Geminids Meteoroid Stream
June 15, 2023

The Geminids meteoroid stream produces one of the most intense meteor showers at Earth. It is an unusual stream in that its parent body is understood to be an asteroid, (3200) Phaethon, unlike most streams, which are formed via ongoing cometary activity. Until recently, our primary understanding of this stream came from Earth-based…

Publication: Proton Equatorial Pitch Angle Distributions in Jupiter's Inner Magnetosphere
June 14, 2023

Protons are seen throughout Jupiter's magnetosphere. Where these protons come from and how they evolve is not well understood. Previous observations by the Galileo spacecraft showed that protons in the vicinity of Europa have properties consistent with charge exchange with a neutral species, which effectively removes the…

Publication: Entropy Defect in Thermodynamics
June 5, 2023

New paper on the axiomatic generalization of thermodynamics for systems with correlations among their constituents, residing either in stationary or nonstationary states.

Analytically, the paper describes the physical foundations of the newly discovered “entropy defect” as a basic concept of thermodynamics. The entropy defect…