Stability of Polytropic Gas Spheres
نویسندگان
چکیده
منابع مشابه
Gravitational instability of isothermal and polytropic spheres
We complete previous investigations on the thermodynamics of self-gravitating systems by studying the grand canonical, grand microcanonical and isobaric ensembles. We also discuss the stability of polytropic spheres in connexion with a generalized thermodynamical approach proposed by Tsallis. We determine in each case the onset of gravitational instability by analytical methods and graphical co...
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Polytropic models play a very important role in galactic dynamics and in the theory of stellar structure and evolution. However, in general, the solution of the Lane-Emden equation can not be given analytically but only numerically. In this paper we give a good analytic approximate solution of the Lane-Emden equation. This approximation is very good for any finite polytropic index n and for the...
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We investigate spherically symmetric, static matter configurations with polytropic equation of state for a class of fðRÞmodels in Palatini formalism and show that the surface singularities recently reported in the literature are not physical in the case of Planck scale modified Lagrangians. In such cases, they are just an artifact of the idealized equation of state used. In fact, we show that f...
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ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 1958
ISSN: 0035-8711,1365-2966
DOI: 10.1093/mnras/118.5.523