Abstract We analysed the shadow cast by charged rotating black hole (BH) in presence of perfect fluid dark matter (PFDM). studied null geodesic equations and obtained BH to see effects PFDM parameter ? , charge Q rotation a it is noticed that size as well shape affected due parameter, parameter. Thus, seen around affects its spacetime. also investigated influence all parameters (PFDM BHs rotati...

Analog gravity models of general relativity seem promising routes to providing laboratory tests of the foundation of quantum field theory in curved space-time. In contrast to general relativity, where geometry of a spacetime is determined by the Einstein equations, in analog models geometry and evolution of analog spacetime are determined by the equations of fluid mechanics. In this paper we st...

We present a reconstruction method for flat Friedman–Robertson–Walker (FRW) spacetime in subclass of Horndeski theory—specifically shiftsymmetric, the kinetic gravity braiding (KGB) theory with non-vanishing conserved current. Choosing form Hubble parameter and density X, we restore functions $$G_2$$ , $$G_3$$ KGB model. In order to determine whether model is free ghosts Laplacian instabilities...

We carry out numerical simulations of the gravitational collapse a rotating perfect fluid with ultrarelativistic equation state $P=\ensuremath{\kappa}\ensuremath{\rho}$, in axisymmetry $2+1$ spacetime dimensions $\mathrm{\ensuremath{\Lambda}}<0$. show that for $\ensuremath{\kappa}\ensuremath{\lesssim}0.42$, critical phenomena are type I, and solution is stationary. The picture $\ensuremath{\...

In the present paper we study a conformally flat generalized Ricci recurrent perfect fluid spacetime with constant scalar as solution of modified $F(R)$-gravity theory. We show that Robertson-Walker is Recurrent if and only it symmetric. The type matter shown to have EoS $\omega=-1$. Some energy conditions are analyzed couple popular toy models $F(R)$-gravity, like $F(R)= R+\alpha R^m $ where $...

In this paper, the effect of electromagnetic field has been investigated on the spherically symmetric collapse with the perfect fluid in the presence of positive cosmological constant. Junction conditions between the static exterior and non-static interior spherically symmetric spacetimes are discussed. We study the apparent horizons and their physical significance. It is found that electromagn...

Einstein’s field equations in general relativity admit a variety of solutions with spacetime singularities. Numerical relativity has recently revealed the properties of somewhat generic spacetime singularities. It has been found that in a variety of systems self-similar solutions can describe asymptotic or intermediate behaviour of more general solutions. The typical example is the convergence ...

The first static spherically symmetric perfect fluid solution with constant density was found by Schwarzschild in 1918. Generically, perfect fluid spheres are interesting because they are first approximations to any attempt at building a realistic model for a general relativistic star. Over the past 90 years a confusing tangle of specific perfect fluid spheres has been discovered, with most of ...