Radial Kippenhahn plot showing the internal profile evolution of the 100 M_⊙ model. The solid black and blue lines are the total and core radii respectively. The black dashed lines track radius of constant q = m/M_tot = 0.1 − 0.9 in increments of 0.1. Additional constant q lines between q = 0.6 and 0.7 are also plotted in the bottom right plot. Blue and red contours are used to show positive (contracting) and negative (expanding) contributions of the local gravitational source term, ϵ_grav. The green shading marks convective regions where |1 − Γ_rad|< 0.1, and β = P_gas/P_tot <  0.1. The four subplots correspond to (a) Inflation during the Main sequence phase (b) Expansion during the MS as the model loses thermal balance just below temperature of log(T_eff/K) ∼3.8 (c) Expansion once the core runs out of hydrogen (d) Inflating layers inside the model during core-He burning.