2006/10/16 by Baojiu Li, M. C. Chu, Ming-Chung Chu · 3 citations
Physics and Astronomy · #Cosmology and Gravitation Theories #Galaxies: Formation, Evolution, Phenomena #Particle physics theoretical and experimental studies #Physics #astro-ph
paper · pdf · doi:10.1103/physrevd.74.104010
published as Phys.Rev. D74 (2006) 104010 · 7 pages, 5 figures; accepted for publication in Phys. Rev. D
arxiv created 2006/10/16 · openalex publication_date 2006/11/07 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We calculate in this article the cosmic microwave background (CMB) and matter power spectra of a class of early f(R) cosmologies, which takes the form of f(R)=R+\ensuremathλ1H02exp[R/(\ensuremathλ2H02)]. Unlike the late-time f(R) cosmologies such as f(R)=R+\ensuremathα(\ensuremath-R)^\ensuremathβ (\ensuremathβ<0), the deviation from \ensuremathΛCDM of this model occurs at a higher redshift (thus the name ``early f(R) cosmology''), and this important feature leads to rather different integrated Sachs-Wolfe (ISW) effect and CMB spectrum. The matter power spectrum of this model is, however, again very sensitive to the chosen parameters, and large scale structure (LSS) observations such as Sloan digital sky survey (SDSS) should constrain the parameter space stringently. We expect that our results are applicable at least qualitatively to other models that produce f(R) modification to GR at earlier times (e.g., redshifts O(10)\ensuremath\lesssimz\ensuremath\lesssimO(1)) than when dark energy begins to dominate---such models are strongly disfavored by data on CMB and matter power spectra.