Comment on “Viable Singularity-Freef(R)Gravity without a Cosmological Constant”
نویسندگان
چکیده
منابع مشابه
Viable singularity-free f(R) gravity without a cosmological constant.
Several authors have argued that self-consistent f(R) gravity models distinct from the cold dark matter model with a cosmological constant (LambdaCDM) are almost ruled out. Confronting such claims, we present a particular two-parameter f(R) model that (a) is cosmologically viable and distinguishable from LambdaCDM, (b) is compatible with the existence of relativistic stars, (c) is free of singu...
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A conjecture stated by Raychaudhuri which claims that the only physical perfect fluid non-rotating non-singular cosmological models are comprised in the Ruiz-Senovilla and Fernández-Jambrina families is shown to be incorrect. An explicit counterexample is provided and the failure of the argument leading to the result is explicitly pointed out. Since the publication of the first non-singular cos...
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ژورنال
عنوان ژورنال: Physical Review Letters
سال: 2009
ISSN: 0031-9007,1079-7114
DOI: 10.1103/physrevlett.103.179001