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arXiv · 1111.5336

Noether gauge symmetry for $f(R)$ gravity in Palatini formalism

Y. Kucukakca·U. Camci
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Abstract

In this study, we consider a flat Friedmann-Robertson-Walker (FRW) universe in the context of Palatini $f(R)$ theory of gravity. Using the dynamical equivalence between $f(R)$ gravity and scalar-tensor theories, we construct a point Lagrangian in the flat FRW spacetime. Applying {\em Noether gauge symmetry approach} for this $f(R)$ Lagrangian we find out the form of $f(R)$ and the exact solution for cosmic scale factor. It is shown that the resulting form of $f(R)$ yield a power-law expansion for the scale factor of the universe.

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Y. Kucukakca, U. Camci. 2012-02-01. Noether gauge symmetry for $f(R)$ gravity in Palatini formalism. https://doi.org/10.1007/s10509-011-0921-5

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