TY - GEN

T1 - Exterior solutions of ultra-compact object candidate from semi-classical gravity

AU - Prasetyo, I.

AU - Ramadhan, H. S.

AU - Sulaksono, A.

N1 - Publisher Copyright:
© 2021 American Institute of Physics Inc.. All rights reserved.
Copyright:
Copyright 2021 Elsevier B.V., All rights reserved.

PY - 2021/3/2

Y1 - 2021/3/2

N2 - In a recent paper by Carballo-Rubio [Phys. Rev. Lett. 120, 061102 (2018)], the author proposed an ultra-compact object model, i.e., a combination of black stars and gravastars, from semi-classical gravity to obtain a generalized Tolman-Oppenheimer-Volkoff (TOV) equation with a new coupling constant lp. The resulting TOV equations have two different forms differentiated by the sign in metric function equation dgtt/dr. In the limit lp 0, the second (respectively, the first) form of the equations from the negative (positive) sign is (is not) going back to the TOV equation. By defining a suitably new constant parameter , the author has found a solution from the first form of obeying boundary conditions. In this work, we investigate the model in a vacuum to obtain exterior solutions for the model. We calculate its exterior solutions using the perturbation method by a small parameter =lp/rs where rs=2GM is the Schwarzschild radius and obtain the Schwarzschild metric as its leading terms. We also investigate its geodesic equations, whose effective potential from our exterior solutions has similar qualitative features as the geodesic of the Schwarzschild metric, i.e., it contains stable and unstable circular orbits.

AB - In a recent paper by Carballo-Rubio [Phys. Rev. Lett. 120, 061102 (2018)], the author proposed an ultra-compact object model, i.e., a combination of black stars and gravastars, from semi-classical gravity to obtain a generalized Tolman-Oppenheimer-Volkoff (TOV) equation with a new coupling constant lp. The resulting TOV equations have two different forms differentiated by the sign in metric function equation dgtt/dr. In the limit lp 0, the second (respectively, the first) form of the equations from the negative (positive) sign is (is not) going back to the TOV equation. By defining a suitably new constant parameter , the author has found a solution from the first form of obeying boundary conditions. In this work, we investigate the model in a vacuum to obtain exterior solutions for the model. We calculate its exterior solutions using the perturbation method by a small parameter =lp/rs where rs=2GM is the Schwarzschild radius and obtain the Schwarzschild metric as its leading terms. We also investigate its geodesic equations, whose effective potential from our exterior solutions has similar qualitative features as the geodesic of the Schwarzschild metric, i.e., it contains stable and unstable circular orbits.

UR - http://www.scopus.com/inward/record.url?scp=85102293742&partnerID=8YFLogxK

U2 - 10.1063/5.0037487

DO - 10.1063/5.0037487

M3 - Conference contribution

AN - SCOPUS:85102293742

T3 - AIP Conference Proceedings

BT - 9th National Physics Seminar 2020

A2 - Nasbey, Hadi

A2 - Fahdiran, Riser

A2 - Indrasari, Widyaningrum

A2 - Budi, Esmar

A2 - Bakri, Fauzi

A2 - Prayitno, Teguh Budi

A2 - Muliyati, Dewi

PB - American Institute of Physics Inc.

T2 - 9th National Physics Seminar 2020

Y2 - 20 June 2020

ER -