A static spherically symmetric perfect fluid solution to model the interior of stars


  • Gabino Estevez Delgado Universidad Michoacana de San Nicolás de Hidalgo https://orcid.org/0000-0003-3491-4639
  • Joaquin Estevez Delgado Universidad Michoacana de San Nicolás de Hidalgo
  • Elivet Aguilar Campuzano Universidad Michoacana de San Nicolás de Hidalgo




General relativity; exact solutions; perfect fluid; relativistic compact stars


An exact solution for modeling the interior of stars with perfect fluid is presented, the geometry of their interior is described by a static and spherically symmetric regular space-time. The hydrostatic functions are physically acceptable for the compactness rate u = GM/c2R ∈ (0, 0.3183497], the speed of sound is a monotonically decreasing function, positive and lower than the speed of light, which implies that the condition of causality is not violated, meanwhile the stability of the solution is guaranteed due to the adiabatic index γ > 3.08387 and it is a monotonically increasing function. The analysis of the solution is presented graphically for specific values of the compactness on the interval u ∈ [0.2509338, 0.3183497] with the minimum value of this interval associated to the neutron star PSR J0348+0432, for observational data which generates the maximum compactness when the radius is minimal R = 12.062 km and the mass is maximum M = 2.05 M¯, generating a value of the central density ρc = 7.520589 × 1017 kg/m3


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How to Cite

G. . Estevez Delgado, J. Estevez Delgado, and E. . Aguilar Campuzano, “A static spherically symmetric perfect fluid solution to model the interior of stars”, Rev. Mex. Fís., vol. 69, no. 3 May-Jun, pp. 030701 1–, May 2023.



07 Gravitation, Mathematical Physics and Field Theory