Growth of cosmic perturbations in the modified f(R, T) gravity

We explore the generalized f(R, T) modified theory of gravity, where the gravitational Lagrangian is a function of Ricci scalar R and the trace of the energy-momentum tensor T . We derive modified field equations to the linear order of perturbations in the context of f(R, T) model. We then investigate the growth of perturbations in the context of f(R, T) modified gravity. Primary numerical investigations based on matter power spectra diagrams indicate a structure growth suppression in f(R, T) gravity, which exhibits consistency with local measurements. Also, we notice that matter-geometry interaction in f(R, T) model would results in the specific feature named as "matter acoustic oscillations"appeared in matter power spectra diagrams. Moreover, we put constraints on the cosmological parameters of f(R, T) model, utilizing current observations, chiefly cosmic microwave background (CMB), weak lensing, supernovae, baryon acoustic oscillations, and redshift-space distortions data. Numerical results based on MCMC calculations imply that f(R, T) is a qualified theory of modified gravity in reconciling Planck CMB data with local probes of large scale structures, by reporting lower values for the structure growth parameter 68 compared to the standard model of cosmology.