Large-scale structure power spectrum from scalar–tensor gravity

This work deals with the computation of power spectrum large-scale structure using dynamical system approach for a multi-fluid universe in scalar-tensor theory gravity. We use $1+3$ covariant to obtain evolution equations and study behavior matter perturbation equations. The is based on equivalence between $f(R)$ gravity find that, power-law $(R^{n})$ models, $1<n<1.3$, we have evolving above general relativistic scale-invariant line. For $n\geq 1.3$, starts constant amplitude then it experiences oscillations eventually saturates at finite amplitude. Such consistent other observations literature. result supports ongoing investigations linear order.