Astronomical Tests for Extended Gravity: Possible Constraints on f(R) with Vanishing Cosmological Constant

Stanislav Alexeyev, Boris Latosh, Vsevolod Echeistov, D. Melikhov, I. Volobuev
2017 EPJ Web of Conferences  
We discuss the predictions of Starobinsky model of f (R)-gravity with vanishing cosmological constant at the scales, typical for galaxies and galaxy clusters. We show that at current observational accuracy there is no significant difference in cut-off radius values for Starobinsky model and general relativity. This occurs from the masses of galaxies (from 10 9 M S un ), till galaxy clusters ones (till 10 18 M S un ). In addition we demonstrate that cut-off radius value dependence against
more » ... ence against Starobinsky model parameter n increases during increasing n for all mass range. Despite the fact that some models provide the cutoff radius value less than in general relativity no any model comes outside the existing observational accuracy frames. Indication of the incomplete astrophysical applicability of GR is the Universe accelerated expansion [4]. This phenomenon is described by a cosmological constant most accurately. As a consequence, the introduction of an additional constant term to the action causes difficulties in matching with the quantum theory [5, 6] . The incomplete applicability of GR in the high-energy regime is indicated by several phenomena. First, GR is not renormalizable [7], therefore, in the quantum regime, it could be treated only as an effective field theory [8] . Further, the construction of self-consistent cosmological models requires the introduction of an inflationary stage, which cannot be obtained directly from GR [9]. To try to solve this problem the gravity models were extended by additional ⋆
doi:10.1051/epjconf/201715805009 fatcat:mv7xs46ymrdwjmthimmxfmvupi