Conformally flat polytropes for anisotropic matter

Abstract

We analyze in detail conformally flat spherically symmetric fluid distributions, satisfying a polytropic equation of state. Among the two possible families of relativistic polytropes, only one contains models which satisfy all the required physical conditions. The ensuing configurations are necessarily anisotropic and show interesting physical properties. Prospective applications of the presented models to the study of super-Chandrasekhar white dwarfs, are discussed.Comment: 9 pages Revtex-4, 6 figures. To appear in Gen. Rel. Grav. Some typos correcte

Cracking of general relativistic anisotropic polytropes

“…Such duplets have been determined in [2] (see figures (3,4) for the case I, and (8,9) for the case II, in that reference). Also, the absolute numerical values of the perturbations of the parameters were taken of the order of 10 −6 , the results are not qualitatively sensitive, to changes in some orders of magnitude, below or above, that figure.…”

Analytical study of anisotropic compact star models

“…Obviously α satisfies Eqs. (43) and (51), while the radial speed of sound satisfies the sufficient condition Eq. (36).…”

“…Several models were given with p r = 0 or prescribed λ. Recently, a conformally flat model with polytropic equation of state was discussed [43]. More solutions have been given by other authors [44,45].…”

Electromagnetic effects on cracking of anisotropic polytropes

“…First, we evaluate 0 , and η for both cases by integrating Eqs. (13), (15), (16), and (17) with boundary conditions [13] …”

“…Herrera and Barreto [12] discussed a general formalism for relativistic isotropic as well as anisotropic polytropes of a spherically symmetric matter distribution and constructed the Lane-Emden equation, which represents the inner structure of compact objects. Herrera et al [13] examined the stability of spherically symmetric anisotropic conformally flat polytropes using the Tolman mass and found that the considered polytropic models are stable. The perturbation technique plays a crucial role in the stability of astrophysical objects.…”