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Related papers: Non-extensive statistics and the stellar polytrope…

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The thermodynamical property of a small cluster including $M$ Hubbard dimers, each of which is described by the two-site Hubbard model, has been discussed within the nonextensive statistics (NES). We have calculated the temperature…

Statistical Mechanics · Physics 2009-11-11 Hideo Hasegawa

The underlying connection between the degrees of freedom of a system and its nonextensive thermodynamic behavior is addressed. The problem is handled by starting from a thermodynamical system with fractal structure and its analytical…

Statistical Mechanics · Physics 2021-09-17 A. Deppman , J. A. S. Lima

We show that the zeroth law of thermodynamics holds within an alternative version of nonextensive statistical mechanics based on {\it incomplete probability distribution}. The generalized zeroth law leads to a generalized definition of…

Statistical Mechanics · Physics 2007-05-23 Qiuping A. Wang

In a first part the scope of classical thermodynamics and statistical mechanics is discussed in the broader context of formal dynamical systems, including computer programmes. In this context classical thermodynamics appears as a particular…

Statistical Mechanics · Physics 2009-11-11 Daniel Pfenniger

Thermodynamical arguments are known to be useful in the construction of physically motivated Lyapunov functionals for nonlinear stability analysis of spatially homogeneous equilibrium steady states in thermodynamically isolated systems.…

Statistical Mechanics · Physics 2019-08-06 Miroslav Bulíček , Josef Málek , Vít Průša

The aim of this study is to construct a simple stellar model with non-uniform polytropic index. We find that the Emden equation cannot deal with the polytrope gas sphere with non-uniform polytropic index in a real star, and then we…

Solar and Stellar Astrophysics · Physics 2022-09-21 Xing Wei

Astrophysical systems differ often in two points from classical thermodynamical systems: 1.) They are open and 2.) gravity is a dominant factor. Both modifies the homogeneous equilibrium structure, known from classical thermodynamics. In…

Astrophysics · Physics 2007-05-23 Daniel Huber

The incomplete nonextensive statistics in the canonical and microcanonical ensembles is explored in the general case and in a particular case for the ideal gas. By exact analytical results for the ideal gas it is shown that taking the…

Statistical Mechanics · Physics 2011-01-17 A. S. Parvan , T. S. Biro

Estimation of the distribution function f and potential Phi of hot stellar systems from kinematical data is discussed. When the functional forms of f and Phi are not specified a priori, accurate estimation of either function requires very…

Astrophysics · Physics 2007-05-23 David Merritt

Polytropic models of stellar winds remain to be useful tools because they allow for a simple description of the energy balance of the expanding plasma without explicitly specifying potentially complex energy transport processes like, e.g.,…

Solar and Stellar Astrophysics · Physics 2026-04-23 L. Westrich , B. Shergelashvili , H. Fichtner , V. N. Melnik

We analyze how the thermal history of the universe is influenced by the statistical description, assuming a deviation from the usual Bose-Einstein, Fermi-Dirac and Boltzmann-Gibbs distribution functions. These deviations represent the…

General Relativity and Quantum Cosmology · Physics 2009-11-07 M. E. Pessah , Diego F. Torres , H. Vucetich

Based on the Tsallis entropy, the nonextensive thermodynamic properties are studied as a q-deformation of classical statistical results using only probabilistic methods and straightforward calculations. It is shown that the constant in the…

Statistical Mechanics · Physics 2007-05-23 Franck Jedrzejewski

A small subset of Galactic O-stars possess surface magnetic fields that alter the outflowing stellar wind by magnetically confining it. Key to the magnetic confinement is that it induces rotational modulation of spectral lines over the full…

Solar and Stellar Astrophysics · Physics 2021-06-23 Florian A. Driessen , Jon O. Sundqvist , Gregg A. Wade

It is natural important question for us to ask what the nonextensive parameter stands for when Tsallis statistics is applied to the self-gravitating systems. In this paper, some properties of the nonextensive parameter and Tsallis…

Adaptation and Self-Organizing Systems · Physics 2015-08-10 Jiulin Du

An ideal mixture of parahydrogen (with nuclear spin K=0) and orthohydrogen (with K=1), in statistical weights 1/4 and 3/4, respectively, is used as a test ground for the existence of non-extensivity in chemical physics. We report on a new…

Statistical Mechanics · Physics 2009-11-07 S. Martinez , F. Pennini , A. Plastino , H. Vucetich

The problem of temperature in nonextensive statistical mechanics is studied. Considering the first law of thermodynamics and a "quasi-reversible process", it is shown that the Tsallis entropy becomes the Clausius entropy if the inverse of…

Statistical Mechanics · Physics 2009-11-11 Sumiyoshi Abe

The nonextensive statistics based on Tsallis entropy have been so far used for the systems composed of subsystems having same $q$. The applicability of this statistics to the systems with different $q$'s is still a matter of investigation.…

Statistical Mechanics · Physics 2007-05-23 Qiuping A. Wang

We numerically determine the entropy for heat-conducting states, which is connected to the so-called excess heat considered as a basic quantity for steady-state thermodynamics in nonequilibrium. We adopt an efficient method to estimate the…

Statistical Mechanics · Physics 2016-08-17 Yoshiyuki Chiba , Naoko Nakagawa

A novel formalism, called H-theory, is applied to the problem of statistical equilibrium of a hierarchical complex system with multiple time and length scales. In this approach, the system is formally treated as being composed of a small…

Statistical Mechanics · Physics 2019-05-06 Giovani L. Vasconcelos , Domingos S. P. Salazar , A. M. S. Macêdo

We derive the nonextensive thermodynamics of an ideal quantum gas composed by bosons and/or fermions with finite chemical potentials. We find agreement with previous works when $\mu \le m$, and some inconsistencies are corrected for…

High Energy Physics - Phenomenology · Physics 2015-06-22 Eugenio Megias , Debora P. Menezes , Airton Deppman