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arXiv · 2401.08254

Probing black hole in Starobinsky-Bel-Robinson gravity with thermodynamical analysis, effective force and gravitational weak lensing

Abstract

In this work, we investigate the effects of plasma and the coupling parameter $\beta>0$, on the thermodynamic properties and weak gravitational lensing by the Schwarzschild-like black hole in the Starobinsky-Bel-Robinson gravity (SBRG). We observe that the horizon radius and the corrected entropy of the Schwarzschild-like black hole in the SBRG are not much sensitive to the parameter $\beta$. On contrary the energy emission rate of the Schwarzschild-like black hole in the SBRG is sensitive to the parameter $\beta$ and decreases with increase in the values of the parameter $\beta$. We see that the Schwarzschild-like black hoe in the SBRG is stable as the thermodynamicl temperature is positive for different values of the parameter $\beta$. Moreover we observe that the deflection angle of photon beam by the black hole in uniform plasma, nonuniform self-interacting scalar plasma and non-singular isothermal gas sphere reduces with the parameter $\beta$, against the impact parameter $b$. We see that the deflection angle enhances with increase in the concentration of the plasma fields for all the three types of plasma media. Further we find that the magnification of the image due to lensing increases in a higher concentration of plasma field. It is interesting to notice that the image magnification in uniform plasma is much higher as compared to the one in nonuniform plasma field. We compare our results with those for the Schwarzschild black hole of General Relativity. Further, effective force is also calculated for the current analysis.

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BibTeXRIS

G. Mustafa, Allah Ditta, Faisal Javed, Farruh Atamurotov, Ibrar Hussain, Bobomurat Ahmedov. 2024-01-16. Probing black hole in Starobinsky-Bel-Robinson gravity with thermodynamical analysis, effective force and gravitational weak lensing. https://arxiv.org/abs/2401.08254

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