2022/12/31 by Gabino Estévez-Delgado, Estevez-Delgado, Gabino, Joaquin Estevez-Delgado +5
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc) #Relativity and Gravitational Theory
paper · pdf · doi:10.48550/arxiv.2301.00210
openalex publication_date 2022/12/31 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Starting from the solution of the Einstein field equations in a static and spherically symmetric spacetime which contains an isotropic fluid, we construct a model to represent the interior of compact objects with compactness rate u=(GM)/(c2R)<0.23577. The solution is obtained by imposing the isotropy condition for the radial and tangential pressures, this generates an ordinary differential equation of second order for the temporal gtt and radial grr metric potentials, which can be solved for a specific function of gtt. The graphic analysis of the solution shows that it is physically acceptable, that is to say, the density, pressure and speed of sound are positive, regular and monotonically decreasing functions, also, the solution is stable due to meeting the criteria of the adiabatic index. When taking the data of mass M=1.44+0.15-0.14M_\odot and radius R=13.02+1.24-1.06km which corresponds to the estimations of the star PSR J0030+045 we obtain values of central density ρc=7.5125× 1017 kg/m3 for the maximum compactness u=0.19628 and of ρc= 2.8411 × 1017 kg/m3 for the minimum compactness u=0.13460, which are consistent with those expected for this type of stars.