For a fully relativistic treatment, the equation of state used interpolates between the equations P = K 1 ρ for small ρ and P = K 2 ρ for large ρ. When this is done, the model radius still decreases with mass, but becomes zero at M limit. This is the Chandrasekhar limit. The curves of radius against mass for the non-relativistic and relativistic models are shown in the graph. They are colored blue and green, respectively. μ e has been set equal to 2. Radius is measured in standard solar radii or kilometers, and mass in standard solar masses.