Constant sound speed and its thermodynamical interpretation in f(Q) gravity

Abstract

On the basis of homogeneous and isotropic Friedmann-Lemaitre-Robertson-Walker (FLRW) geometry, solutions to the issues of cosmic acceleration and dark energy are being put forth within the context of f(Q) gravity. We take into account a power law f(Q) model using f(Q)=αQn, where α and n are free model parameters. In the current scenario, we may establish the energy density and pressure for our f(Q) cosmic model by applying the constant sound speed parameterizations, i.e., ϑs2=β, where a barotropic cosmic fluid is described in terms of β. The field equations are then derived, and their precise solutions are established. We obtain the constraints on the model parameters using the updated Hubble (Hz) data sets consisting of 31 data points, the recently published Pantheon samples (SNe) with 1048 points, and Baryon acoustic oscillations (BAO) data sets. We also examine the physical behavior of the deceleration parameter, the equation of state (EoS) parameter, the statefinder diagnostic, and the Om diagnostic. We conclude that our f(Q) cosmic model predicts a transition in the universe from deceleration to acceleration. Further, to investigate the feasibility of the model, we discussed some of its thermodynamic aspects.