Extension of Isotropic Solutions into Anisotropic Domain Via Gravitational Decoupling Approach

Abstract

In this thesis, we study known charged and uncharged isotropic Heintzmann solution and Durgapal IV solution and extend it to its well anisotropic domain by manipulating gravitational decoupling through extended geometric deformation (EGD) approach. We employ linear transformation on both metric potentials and convert the single set of EFEs into two less-complicated subsystems. The first one is related to the standard Einstein-Maxwell field equations (EFEs), while the other one is related to additional source. The matching conditions at the stellar surface are discussed in detail, where outer geometry is representedbyReissner-Nordstromsolutioninthepresenceandschwarzschild solution in the absence of charge and also evaluate the expressions for thermodynamical quantities ρtot, ptot r and ptot t using mimic constraint and equation of state (EoS).We discuss the physical properties of the stellar model. Physical analysis is carried out using different physical indicators i.e, energy conditions, equilibrium equation, casualty condition, Herrera’s cracking concept, adiabatic index, compactness and surface redshift. In order to check the viability of the anisotropic version of the solution, we consider three different realistic stars, namely SAXJ1808.4 − 3652, SMCX − 4 and PSRJ1614 − 2230, and analyze the behavior of the model against different values of intensity parameter, i.e., γ = 0, 0.2 and 0.3 and also evaluate the graphical behavior of compact star PSRJ1614−2230 againstdifferentvaluesof γ = 0.25, 0.55 and 0.75 fordifferent model.