So I have recently watched a simulation of dark matter density and gas temperature evolution in a universe. However I couldn't find description of under what assumptions it was was made and what it is telling us.
Simulation is here: http://www.illustris-project.org/movies/illustris_movie_cube_sub_frame.mp4
The description next to the video:
Time evolution of a 10Mpc (comoving) cubic region within Illustris, rendered from outside. The movies shows on the left the dark matter density field, and on the right the gas temperature (blue: cold, green: warm: white: hot). The rapid temperature fluctuations around massive haloes are due to radiative AGN feedback that is most active during quasar phases. The larger 'explosions' are due to radio-mode feedback.
Maybe some of you had spent some time thinking about these things and could answer some of my questions about simulation?
1) It seems where we have large dark matter density, we also have large temperature, meaning large matter density, is these are the regions new galaxies or stars forms?
2) It seems that dark matter density just builds up slowly in this net but do not move anywhere, does it mean that dark matter is slow? (non relativistic)
3) Stellar mass counter is increasing meaning that new suns are forming. Does this means that initially universe were more uniform in matter density, however some regions attracted more matter and started forming galaxies?