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What does the nonextensive parameter q stand for in self-gravitating systems ?

Jiulin Du
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Abstract

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 equilibrium distribution for the self-gravitating system are discussed in the framework of nonextensive kinetic theory. On the basis of the solid mathematical foundation, the nonextensive parameter can be expressed by a formula with temperature gradient and the gravitational potential and can be presented the physical meaning with regard to the non-isothermal (nonequilibrium stationary state) nature of the systems with long-range interactions. We come to the conclusion that Tsallis equilibrium distribution is corresponding to the physical state of self-gravitating system at the hydrostatic equilibrium.

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Jiulin Du. 2010-04-06. What does the nonextensive parameter q stand for in self-gravitating systems ?. https://doi.org/10.1007/s10509-006-9199-4

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