Astrophysical implications of an eternal homogeneous gravitational collapse model with a parametrization of expansion scalar

Abstract

In this study, we continue our previous work (Annu et al., 2023) by introducing a novel parametrization of the expansion scalar $\Theta $ as a rational function of cosmic time $t$. The paper provides a comprehensive analysis of a homogeneous gravitational collapsing system, wherein the exact solutions of the Einstein field equations (EFEs) are determined using a new parametrization of $\Theta$ in a model-independent way. The model is especially significant for the astrophysical applications because we have addressed the physical and geometrical quantities of the model in terms of Schwarzschild mass $M$. We have estimated the numerical value of the model parameter involved in the functional form of $\Theta$-parametrization using the masses \& radii data of some massive stars namely, Westerhout 49-2, BAT99-98, R136a1, R136a2, WR 24, Pismis 24-1, $\lambda$ Cephei, $\alpha$ Camelopardalis, $\beta$ Canis Majoris. We have presented theoretical investigations about such astrophysical stellar systems. The formation of apparent horizon is also studied for the collapsing system, and it has been shown that our model produces a continuing collapsing scenario of star (an eternal collapsing object).