The Logotropic Dark Fluid: Observational and Thermodynamic Constraints

Understand

We have considered a spatially flat, homogeneous and isotropic FLRW Universe filled with a single fluid, known as logotropic dark fluid (LDF), whose pressure evolves through a logarithmic equation of state.

• We use the recent Pantheon SNIa and cosmic chronometer datasets to constrain the parameters of this model, the present fraction of dark matter $\Omega_{m0}$ and the Hubble constant $H_0$.
• We find that the mean values of these parameters are $\Omega_{m0}=0.288\pm 0.012$ and $H_{0}=69.652\pm 1.698~{\rm km/s/Mpc}$ at the $1\sigma$ CL.
• We also find that the LDF model shows a smooth transition from the deceleration phase to acceleration phase of the universe in the recent past.