Growth_Index_Of_Viable_F_R_Models

Constructed for the study of viable dark energy f(R) models and the extraction of the expected enhancement or suppression of gravitational waves. This Mathematica notebook was devised in order to ascertain the validity of various f(R) models in the late-time era by making a direct comparison between the results extracted and the ΛCDM model. Afterwards the growth index for gravitational waves is briefly evaluated. For the current model, a power-law f(R) model is used however is it presented with the help of a Legendre function. By introducing a single free parameter which is essentially a mass scale and choosing proper initial conditions for Hubble by taking into consideration the numerical value of the cosmological constant, a compatible with the observations model is extracted. Afterwards it is showcased that the growth factor becomes in fact positive therefore suppresion of the intensity of gravitational waves for the model at hand is expected. The code is quite flexible and various f(R) models can be used and tested with perhaps a slit modification of the redshift integration area. The notebook is free for use and distribution.