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Constraints on Non-Singular Cosmological Models with Quadratic Lagrangians

R. Colistete, Jr.
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Abstract

We consider the generalized set of theories of gravitation whose Lagrangians contain the term $R^{2}$ : $L=\sqrt{-g}(R+βR^{2})$. Inserting the RW metric with an imposed non-singular and inflationary behaviour of the scale factor $a(t)$, and using a arbitrary perfect fluid, we study the properties of $ρ$ and $p$ in this context. By requiring the positivity of the energy density, as well as real and finite velocity of sound, we can obtain the range of values of $β$ that ensure the inflationary behaviour and absence of singularity.

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R. Colistete, Jr.. 2002-05-07. Constraints on Non-Singular Cosmological Models with Quadratic Lagrangians. https://doi.org/10.1142/9789812777386_0147

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