相关论文: On surface tension for compact stars
Quartic gravity theory is considered with the Einstein-Hilbert Lagrangean $R+aR^{2}+bR_{\mu \nu}R^{\mu \nu},$ $R_{\mu \nu}$ being Ricci\'s tensor and R the curvature scalar. The parameters $a$ and $b$ are taken of order 1 km$^{2}.$…
We derive upper and lower limits for the basic physical parameters (mass-radius ratio, anisotropy, redshift and total energy) for arbitrary anisotropic general relativistic matter distributions in the presence of a cosmological constant.…
Employing $f(T)$ gravity, where $T$ is the torson, we have developed a new model of an anisotropic compact star in this work. Tolman-Kuchowicz (TK) metric potential has been used to solve the set of field equations. Furthermore, the…
We systematically examine the compactness of neutron stars as Tolman VII solutions in scalar-tensor theory of gravity. As a result, when the coupling constant is confined to values provided by astronomical observations we show that the…
In this article we try to present spherically symmetric isotropic strange star model under the framework of $f(R,\mathcal{T})$ theory of gravity. To this end, we consider that the Lagrangian density is an arbitrary linear function of the…
We provide a set of general tools to study the problem of stellar equilibrium in any gravitational theory in which spherically symmetric spacetimes satisfy master field equations taking the form of an equality between an identically…
In this paper we present a strange stellar model using Tolman $V$ type metric potential employing simplest form of the MIT bag equation of state (EOS) for the quark matter. We consider that the stellar system is spherically symmetric,…
By assuming a particular mass function we find new exact solutions to the Einstein field equations with an anisotropic matter distribution. The solutions are shown to be relevant for the description of compact stars. A distinguishing…
In this investigation we examine the astrophysical consequences of the influence of pressure anisotropy on the physical properties of observed pulsars within the background of $f(Q,T)$ gravity by choosing a specific form $f(Q, T)=\psi_1\, Q…
Heavy-neutrino (or neutralino) stars are studied using the general relativistic equations of hydrostatic equilibrium and the relativistic equation of state for degenerate fermionic matter. The Tolman-Oppenheimer-Volkoff equations are then…
This thesis investigates compact astrophysical objects within modified theories of gravity, focusing on neutron stars and strange stars. The work studies their internal structure, equilibrium, and stability in gravitational frameworks based…
Einstein-Cartan gravity is a close historical sibling of general relativity that allows for spacetime torsion. As a result, angular momentum couples to spacetime geometry in a similar way to energy. While consequences of this are well…
We study relativistic stars in the simplest model of the de Rham-Gabadadze-Tolley massive gravity which describes the massive graviton without ghost propagating mode. We consider the hydrostatic equilibrium, and obtain the modified…
In the context of f(R)=R + alpha R^2 gravity, we study the existence of neutron and quark stars with no intermediate approximations in the generalised system of Tolman-Oppenheimer-Volkov equations. Analysis shows that for positive alpha's…
We obtain an exact analytical solution to Einstein's field equations assuming a non-linear equation-of-state and a particular mass function. Our solution describes the interior of anisotropic color flavor locked strange quark stars. All…
We investigate whether compact stars having Tolman-like interior geometry admit conformal symmetry. Taking anisotropic pressure along the two principal directions within the compact object, we obtain physically relevant quantities such as…
Unitarity of evolution in gravitational collapses implies existence of macroscopic stable horizonless objects. With such objects in mind, we study the effects of anisotropy of pressures on the stability of stars. We consider stars in four…
We present a generalization of Rastall's gravity in which the conservation law of the energy-momentum tensor is altered, and as a result, the trace of the energy-momentum tensor is taken into account together with the Ricci scalar in the…
Neutron stars could contain a mixture of ordinary nuclear matter and dark matter, such that dark matter could influence observable properties of the star, such as its mass and radius. We study these dark matter admixed neutron stars for two…
Multi-messenger astronomical observations of neutron stars, together with more precise calculations and constraints coming from dense matter microphysics, are generating tension with regard to equations of state models used to describe…