Related papers: Comment to ''On Anisotropic Dark Energy Stars''
We investigate the conditions for the (in)stability of the isotropic pressure condition in collapsing spherically symmetric, dissipative fluid distributions. It is found that dissipative fluxes, and/or energy density inhomogeneities and/or…
Most parametrizations for dark energy involve the equation of state $w$ of the dark energy. In this work, we choose the pressure of the dark energy to parametrize. As $p = constant$ essentially gives a cosmological constant, we use the…
The formalism in order to obtain the Dark Energy equation of state is extended to non-flat universes and we consider the inequalities that must be satisfied by Phantom Dark Energy in this case. We show that due to a non-vanishing spatial…
To justify the twenty years old distant Ia Supernova observations which revealed to us that our universe is experiencing a late time cosmic acceleration, propositions of existence of exotic fluids inside our universe are made. These fluids…
A dark energy with a negative energy density in the past can simultaneously address various cosmological tensions, and if it is to be positive today to drive the observed acceleration of the universe, we show that it should have a pole in…
The literature suggests that dark energy is responsible for the accelerating expansion of the universe due to its negative pressure, therefore, dark energy can be used as a possible option to prevent the gravitational collapse of compact…
This review on dark energy is intended for a wider audience, beginners as well as experts. It contains important notes on various aspects of dark energy and its alternatives. The section on Newtonian cosmology followed by heuristic…
We present a class of exact solutions of Einstein's gravitational field equations describing spherically symmetric and static anisotropic stellar type configurations. The solutions are obtained by assuming a particular form of the…
Compact objects have an intrinsic anisotropy due to the presence of strong magnetic fields that cause considerable modifications on the equations of state (EoS). In this work, we study the impact of this anisotropy in the size and shape of…
New exact solutions of Einstein's field equations for charged stellar models by assuming linear equation of state $ P_r=A(\rho-\rho_{a}) $, where $ P_r $ is the radial pressure and $ \rho_{a} $ is the surface density. By assuming $…
We show that it is possible to obtain credible static anisotropic spherically symmetric matter configurations starting from known density profiles and satisfying a nonlocal equation of state. These particular types of equation of state…
We consider a self-consistent system of Bianchi type-I (BI) gravitational field and a binary mixture of perfect fluid and dark energy. The perfect fluid is taken to be the one obeying the usual equation of state, i.e., $p = \zeta \ve$, with…
The purpose of this paper is to study the effects of dark energy on dynamics of the collapsing fluid within the framework of metric f(R) gravity. The fluid distribution is assumed to be locally anisotropic and undergoing dissipation in the…
The stability of static uncharged spheres with anisotropic internal stresses is studied in general relativity. It has been noticed that pressure anisotropy plays an important role for stability of stellar structure. It is shown that radial…
Perturbative Quantum Chromodynamics (pQCD) corrections and color superconductivity predict that strongly interacting matter can reveal new physical phenomena under extreme conditions. Taking into account these interaction effects, we…
In this latter author would like to consider interaction between a dark energy based on Generalized Uncertainty Principle (GUP) and a Dark Matter described by effective EoS: $P =…
In this paper, we have investigated an anisotropic cosmological model in $f(Q)$ gravity with string fluid in LRS Bianchi type-I universe. We have considered the arbitrary function $f(Q)=Q+\alpha\sqrt{~Q}+2\Lambda$ where $\alpha$ is model…
The origin and nature of dark energy is one of the most significant challenges in modern science. This research aims to investigate dark energy on astrophysical scales and provide a cosmology-independent method to measure its…
Since the discovery of the accelerated expansion of the Universe, the constraints on the equation of state $w_\text{DE}$ of dark energy, the stress-energy component responsible for the acceleration, have tightened significantly. These…
Understanding the role of pressure anisotropy and dissipation is crucial for modelling compact objects' internal structure and observable properties. In this work, we reinterpret local pressure anisotropy in relativistic stellar structures…