Approximate spacetime for neutron stars

  • Francisco Frutos-AlfaroEmail author
Research Article


An approximate realistic metric representing the spacetime of neutron stars is obtained by perturbing the Kerr metric. This metric has five parameters, namely the mass, spin or angular momentum, mass quadrupole, spin octupole and mass hexadecapole. Moreover, a version of the Hartle–Thorne metric containing these parameters is constructed by means of a series transformation between these spacetimes and solving the Einstein field equations. The form of the Pappas metric in Schwarzschild spherical coordinates is found. The three relativistic multipole structures are compared.


Relativistic multipole moments Neutron stars Stationary spacetimes 



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Authors and Affiliations

  1. 1.School of Physics, Space Research Center and Laboratory of Theoretical Physics and Computation of the University of Costa Rica, San JoséSan PedroCosta Rica

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