Anisotropic cosmological solutions in $$R + R^2$$ R + R 2 gravity
نویسندگان
چکیده
منابع مشابه
Strong energy condition in R+R2 gravity.
In this paper, we study Raychaudhuri's equation in the background of R + βR 2 gravity with a phenomenological matter (ρ ∝ a(t) −n). We conclude that even though the Strong Energy Condition (S.E.C.) for Einstein's gravity, which guarantees singularity, is n ≥ 2 for ρ ∝ a(t) −n , a perturbative analysis of Raychaudhuri's equation in the background of R+βR 2 gravity reveals that the big bang singu...
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ژورنال
عنوان ژورنال: The European Physical Journal C
سال: 2018
ISSN: 1434-6044,1434-6052
DOI: 10.1140/epjc/s10052-018-5778-0