Observational Constraints on Model with specific q

Abstract

We place observational constraints on an FLRW cosmological model in $f(R,L_m)$ gravity with a specific deceleration parameter that depends on the scale factor. This form of the deceleration parameter has been discussed by authors in several papers, but none of them have applied observations to constrain the variables of the model. We carry this out with the cosmic chronometer, supernovae and the baryon acoustic oscillation datasets. The optimum values for the relevant parameters are found and used to plot the kinematical and physical parameters of the model. Although the model tends to the standard Lambda cold dark matter model at late times, there are several issues with the model concerning the values of some of the parameters and the energy conditions. The transition redshift of the model does not match with Planck data. The equation of state parameter indicates that the model falls into the category of phantom dark energy, which is not well supported by observations. Thus, the model does not seem viable.