2009/11/30 by Eugeny Babichev, E. Babichev, D. Langlois +1 · 122 citations
Mathematics · Physics and Astronomy · #Astrophysics #Black Holes and Theoretical Physics #Cosmology #Cosmology and Gravitation Theories #Curvature #Dark energy #Equation of state #Geometry #Hubble's law #Mathematical physics #Mathematics #Neutron star #Physics #Quantum mechanics #Scalar curvature #Solar and Space Plasma Dynamics #Stars #astro-ph.CO #gr-qc #hep-th
paper · pdf · doi:10.1103/physrevd.81.124051
published in Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D. Particles and fields 81(12) (American Physical Society) · 20 pages, 10 Figs, revtex4; v2. minor corrections and changes; v3: a few changes, matches published version
openalex publication_date 2010/06/30 · arxiv created 2010/08/04 · arxiv updated 2015/03/13 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We study relativistic stars in the context of scalar-tensor theories of gravity that try to account for the observed cosmic acceleration and satisfy the local gravity constraints via the chameleon mechanism. More specifically, we consider two types of models: scalar-tensor theories with an inverse power law potential and f(R) theories. Using a relaxation algorithm, we construct numerically static relativistic stars, both for constant energy density configurations and for a polytropic equation of state. We can reach a gravitational potential up to \ensuremathΦ\ensuremath∼0.3 at the surface of the star, even in f(R) theories with an ``unprotected'' curvature singularity. However, we find static configurations only if the pressure does not exceed one third of the energy density, except possibly in a limited region of the star (otherwise, one expects tachyonic instabilities to develop). This constraint is satisfied by realistic equations of state for neutron stars.