Interior solutions of relativistic stars with anisotropic matter in scale-dependent gravity

Abstract

We obtain well behaved interior solutions describing hydrostatic equilibrium of anisotropic relativistic stars in scale-dependent gravity, where Newton’s constant is allowed to vary with the radial coordinate throughout the star. Assuming (1) a linear equation-of-state in the MIT bag model for quark matter, and (2) a certain profile for the energy density, we integrate numerically the generalized structure equations, and we compute the basic properties of the strange quark stars, such as mass, radius and compactness. Finally, we demonstrate that stability criteria as well as the energy conditions are fulfilled. Our results show that a decreasing Newton’s constant throughout the objects leads to slightly more massive and more compact stars.

Anisotropic stars made of exotic matter within the complexity factor formalism

“…The last condition has also been significantly investigated along years introducing, via alternative ansatzs, several concrete forms of the anisotropy Π ≡ P ⊥ − P r and different equations of state (see for instance [49,[80][81][82][83][84][85][86][87][88][89][90][91] and references therein). Given that a profound comprehension of the idea of complexity is still under construction, the connection between Π (or more precisely, any equation of state…”

Anisotropic Quark Stars with an Interacting Quark Equation of State within the Complexity Factor Formalism

“…Thus, for a given density profile ρ(r), we can compute the anisotropic factor for a self-gravitating system. Notice that the classical formalism, i.e., selecting a suitable form of the anisotropic factor by hand (among other alternatives), has also been significantly investigated over the years (see, for instance, [29,43,[57][58][59][60][61][62][63][64][65][66][67] and the references therein). As the complexity factor formalism in the context of relativistic stars is so helpful, we will follow this idea and contrast the results obtained following such an approach with solutions coming from the canonical method, i.e., taking by hand the anisotropic factor, for instance.…”

Generalized compact star models with conformal symmetry

“…Stellar models have been investigated in gravity theories other than general relativity. Some of these studies include R 2 gravity [62], f (R, T ) gravity [63,64], scaledependent gravity [65], Rastall gravitational models [66], and also Lovelock gravity [67]. The approach followed in these papers may be treated as a complement to the symmetry approach.…”