2023/03/11 by Annu Jaiswal, Rajesh Kumar, Jaiswal, Annu +5 · 1 citation
Physics and Astronomy · #Cosmology and Gravitation Theories #Galaxies: Formation, Evolution, Phenomena #Black Holes and Theoretical Physics
paper · pdf · doi:10.1140/epjc/s10052-023-11672-y
Abstract In this study, we continue our previous work (Annu et al. 2023) by introducing a novel parametrization of the expansion scalar Θ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>Θ</mml:mi> </mml:math> as a rational function of 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 Θ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>Θ</mml:mi> </mml:math> 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 Θ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>Θ</mml:mi> </mml:math> -parametrization using the masses and radii data of some massive stars namely, Westerhout 49-2, BAT99-98, R136a1, R136a2, WR 24, Pismis 24-1, λ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>λ</mml:mi> </mml:math> Cephei, α <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>α</mml:mi> </mml:math> Camelopardalis, β <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>β</mml:mi> </mml:math> Canis Majoris. We have presented theoretical investigations about such astrophysical stellar systems. The formation of an 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).