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arXiv · 0804.3449

Noether symmetry in $f(R)$ cosmology

Babak Vakili
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Abstract

The Noether symmetry of a generic $f(R)$ cosmological model is investigated by utilizing the behavior of the corresponding Lagrangian under the infinitesimal generators of the desired symmetry. We explicitly calculate the form of $f(R)$ for which such symmetries exist. It is shown that the resulting form of $f(R)$ yields a power law expansion for the cosmological scale factor. We also obtain the effective equation of state parameter for the corresponding cosmology and show that our model can provide a gravitational alternative to the quintessence.

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Babak Vakili. 2008-05-17. Noether symmetry in $f(R)$ cosmology. https://doi.org/10.1016/j.physletb.2008.05.008

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