Animation of the formation of the first filament

Movie caption:

The movie (firststar.avi) shows how gravity leads to the formation of higher and lower density structures from an initially almost perfectly smooth Universe. The colour shading is a measure of gas density, time is measured from the Big Bang, and a length scale of 30kpc (90 000 light years) is indicated. The object does not rotate, but the camera rotates around it to make it easier to see the 3-dimensional structure of the forming object.

The first high density structure you see forming are nearly planar sheets. As the density in the sheets increases, the sheet warps and forms a long filament. Stars will form when the filament fragments. Once the filament collapses, the stars will collide to form a massive black hole.

We assumed that the dark matter that dominates the matter content of the Univser, is a gravitino particle. Such Warm Dark Matter prevent small-scale structures from forming, which is why the filament has little or no substructure. This is very different from the more usual Cold Dark Matter scenario, where stars form in small, spherical dark matter concentrations.

These simulations were performed on the Cosmology Machine at the Institute for Computational Cosmology, Durham University, by Liang Gao
and Tom Theuns.

 

Temperature and density map of the first filament at z=23 (multi-projections, click for raw size images)