Talk:Dynamical time scale

Dynamical and Free-Fall Time
The article seems to indicate that dynamical and free-fall times are the same. However, they are not. The article should be changed to reflect this. Privong (talk) 22:56, 23 January 2008 (UTC)


 * Well, if you know how they differ, change the article. --Neo (talk) 08:29, 24 January 2008 (UTC)

Stellar Astrophysics Formula
The formula was recently changed to $$ \tau_{dynamical} \simeq \frac{R}{v} = \sqrt{\frac{R^3}{2GM}} $$ by an anon. I have in my Astronomy notes that the formula is equal to $$ \tau_{dyn} \simeq \sqrt{\frac{R^3}{GM}} \simeq \frac{1}{\sqrt{G\langle\rho\rangle}} $$. Does anyone know which one is right? I can't seem to find a reference for one way or the other. --pie4all88 (talk) 08:01, 28 January 2008 (UTC)