The gravitational field of a star in quadratic gravity
Abstract
The characterization of the gravitational field of isolated objects is still an open question in quadratic theories of gravity. We study static equilibrium solutions for a selfgravitating fluid in extensions of General Relativity including terms quadratic in the Weyl tensor C_{μνρσ} and in the Ricci scalar R, as suggested by oneloop corrections to classical gravity. By the means of a shooting method procedure we link the total gravitational mass and the strength of the Yukawa corrections associated with the quadratic terms with the fluid properties at the center. It is shown that the inclusion of the C_{μνρσ}^{μνρσ} coupling in the lagrangian has a much stronger impact than the R^{2} correction in the determination of the radius and of the maximum mass of a compact object. We also suggest that the ambiguity in the definition of mass in quadratic gravity theories can conveniently be exploited to detect deviations from standard General Relativity.
 Publication:

Journal of Cosmology and Astroparticle Physics
 Pub Date:
 August 2021
 DOI:
 10.1088/14757516/2021/08/050
 Bibcode:
 2021JCAP...08..050B
 Keywords:

 modified gravity;
 neutron stars;
 quantum gravity phenomenology