 Adiabatic pressure support during gravitational collapse

With fixed mass and homologous scale $L$, adiabatic pressure obeys $p\propto L^{-3\gamma }$. Its support relative to gravitational energy scales as $p{L}^3/|W_g|\propto L^{4-3\gamma }$. Pressure becomes relatively stronger on contraction for $\gamma >4/3$, weaker for $\gamma <4/3$ and has the same scaling at $\gamma =4/3$.