Figure 3 - uploaded by Njabulo Mkhize
Content may be subject to copyright.
depicts the sound of speed value versus the radial r coordinate. The profile satisfies the condition 0 ≤ dp dρ ≤ 1, as demanded for causality. Figure 4 exhibits the energy conditions which are all positive inside the sphere. In figure 5 we provide a plot for the equation of state, expressing the pressure as a function of the density. It is a smooth singularity free function within the star's radius. A plot of the gravitational mass is displayed in figure 6. This reveals a smooth increasing function with the increasing radius as is expected. The compactification parameter (Figure 7) plot is an increasing function most importantly satisfying the inequality mass radius < 4 9 . Finally, we consider the redshift profile (Figure 8) 

depicts the sound of speed value versus the radial r coordinate. The profile satisfies the condition 0 ≤ dp dρ ≤ 1, as demanded for causality. Figure 4 exhibits the energy conditions which are all positive inside the sphere. In figure 5 we provide a plot for the equation of state, expressing the pressure as a function of the density. It is a smooth singularity free function within the star's radius. A plot of the gravitational mass is displayed in figure 6. This reveals a smooth increasing function with the increasing radius as is expected. The compactification parameter (Figure 7) plot is an increasing function most importantly satisfying the inequality mass radius < 4 9 . Finally, we consider the redshift profile (Figure 8) 

Source publication
Preprint
Full-text available
We investigate the behaviour of the Tolman metrics within the formalism of the trace-free (or unimodular) gravity. While this approach is similar to the standard Einstein field equations, some subtlety arises. The effective number of independent field equations is reduced by one on account of the density and pressure appearing as an inseparable ent...