# Evolution of density perturbations in f(R) theories of gravity

@article{CruzDombriz2008EvolutionOD, title={Evolution of density perturbations in f(R) theories of gravity}, author={Alvaro de la Cruz-Dombriz and Antonio Dobado and Antonio L{\'o}pez Maroto}, journal={Physical Review D}, year={2008}, volume={77}, pages={123515} }

In the context of f(R) theories of gravity, we study the evolution of scalar cosmological perturbations in the metric formalism. Using a completely general procedure, we find the exact fourth-order differential equation for the matter density perturbations in the longitudinal gauge. In the case of sub-Hubble modes, the expression reduces to a second-order equation which is compared with the standard (quasistatic) equation used in the literature. We show that for general f(R) functions the…

## 96 Citations

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