So yes, gas dynamics play a big role in the evolution of merging
galaxies. references? try the two references i've been pushing
throughout this thread: Barnes & Hernquist, Annual Reviews of Astronomy
and Astrophysics 1992, and the same authors in Physics today last spring
sometime (Steinn, do you remember that reference?).
Physics Today, March 1993. There was also a Scientific American
article about 3 years ago, can't remember the exact date.
For the nitty-gritty, what-does-it-all-mean and what do you
get out of the simulations, see any of several authors in
recent ApJ, I'd personally point to Mihos+various and Weil+various
and references therein, but that is local bias :-)
* Steinn Sigurdsson Lick Observatory *
* steinly@lick.ucsc.edu "standard disclaimer" *
* The laws of gravity are very,very strict *
* And you're just bending them for your own benefit - B.B. 1988*