2008/06/04 by C. S. J. Pun, Zoltán Kovács, Z. Kovacs +2 · 6 citations
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Pulsars and Gravitational Waves Research #astro-ph #gr-qc #hep-th
paper · pdf · doi:10.1103/physrevd.78.024043
published as Phys.Rev.D78:024043,2008 · 21 pages, 3 figures, accepted for publication in PRD
arxiv created 2008/06/04 · openalex publication_date 2008/07/25 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We consider the basic physical properties of matter forming a thin accretion disc in the static and spherically symmetric space-time metric of the vacuum f(R) modified gravity models. The Lagrangian of the generalized gravity theory is also obtained in a parametric form, and the conditions of the viability of the model are also discussed. The exact Schwarzschild-type solution of the gravitational field equations in the f(R) gravity contains a linearly increasing term, as well as a logarithmic correction, as compared to the standard Schwarzschild solution of general relativity, and it depends on four arbitrary integration constants. The energy flux and the emission spectrum from the accretion disk around the f(R) gravity black holes are obtained, and they are compared to the general relativistic case. Particular signatures can appear in the electromagnetic spectrum, thus leading to the possibility of directly testing modified gravity models by using astrophysical observations of the emission spectra from accretion disks.