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@Article{AkarsuKaKuNuÖzSh:2020:ThFeOb,
               author = "Akarsu, {\"O}zg{\"u}r and Katirci, Nihan and Kumar, Suresh and 
                         Nunes, Rafael da Costa and {\"O}zt{\"u}rk, Burcu and Sharma, 
                         Shivani",
          affiliation = "{Istanbul Technical University} and {Istanbul Technical 
                         University} and {BITS Pilani} and {Instituto Nacional de Pesquisas 
                         Espaciais (INPE)} and {Istanbul Technical University} and {BITS 
                         Pilani}",
                title = "Rastall gravity extension of the standard \Λ CDM model: 
                         theoretical features and observational constraints",
              journal = "European Physical Journal C",
                 year = "2020",
               volume = "80",
               number = "11",
                pages = "e1050",
                month = "Nov.",
             abstract = "We present a detailed investigation of the Rastall gravity 
                         extension of the standard CDM model. We review the model for two 
                         simultaneous modifications of different nature in the Friedmann 
                         equation due to the Rastall gravity: the new contributions of the 
                         material (actual) sources (considered as effective source) and the 
                         altered evolution of the material sources. We discuss the 
                         role/behavior of these modifications with regard to some low 
                         redshift tensions, including the so-called H0 tension, prevailing 
                         within the standard CDM. We constrain the model at the level of 
                         linear perturbations, and obtain the first constraints through a 
                         robust and accurate analysis using the latest full Planck cosmic 
                         microwave background (CMB) data, with and without including baryon 
                         acoustic oscillations (BAO) data. We find that the Rastall 
                         parameter (null for general relativity) is consistent with zero at 
                         68% CL (with a tendency towards positive values, \−0.0001 
                         << 0.0007 (CMB+BAO) at 68% CL), which in turn implies no 
                         significant statistical evidence for deviation from general 
                         relativity, and also a precision of O(10\−4) for the 
                         coefficient \−1/2 of the term g\μ\ν R in the 
                         Einstein field equations of general relativity (guaranteeing the 
                         local energy-momentum conservation). We explore the consequences 
                         led by the Rastall gravity on the cosmological parameters in the 
                         light of the observational analyses. It turns out that the 
                         effective source, with a present-day density parameter X0 = 
                         \−0.0010±0.0013 (CMB+BAO, 68% CL), dynamically screens the 
                         usual vacuum energy at high redshifts, but this mechanism barely 
                         works due to the oppoa e-mail: akarsuo@itu.edu.tr b e-mail: 
                         nihan.katirci@itu.edu.tr c e-mail: 
                         suresh.kumar@pilani.bits-pilani.ac.in (corresponding author) d 
                         e-mail: rafadcnunes@gmail.com e e-mail: ozturkburc@itu.edu.tr f 
                         e-mail: p20170025@pilani.bits-pilani.ac.in sition by the altered 
                         evolution of cold dark matter. Consequently, two simultaneous 
                         modifications of different nature in the Friedmann equation by the 
                         Rastall gravity act against each other, and do not help to 
                         considerably relax the low redshift tensions, including the 
                         so-called H0 tension. Our results may offer a guide for the 
                         research community that studies the Rastall gravity in various 
                         aspects of gravitation and cosmology.",
                  doi = "10.1140/epjc/s10052-020-08586-4",
                  url = "http://dx.doi.org/10.1140/epjc/s10052-020-08586-4",
                 issn = "1434-6044",
             language = "en",
           targetfile = "Akarsu_rastall.pdf",
        urlaccessdate = "18 abr. 2021"
}


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