|Ph.D Student||Leonid Chuzhoy|
|Subject||Non-linear Processes in Structure Formation|
|Department||Department of Physics||Supervisor||Full Professor Nusser Adi|
The purpose of this research is to investigate different stages and aspects of large-scale structure formation. In particular it focuses on the dependence of macroscopic properties of matter, such as density and velocity distribution, on its microscopic properties (i.e. particle mass, charge and interaction cross-section). First, we study the evolution of the collisional baryonic matter in the non-linear regime as opposed to the evolution of collisionless cold dark matter component. Similarity solutions are found for evolution of density perturbations that have the form of the power law. For steep positive perturbations the gas follows closely the dark matter, while shallow perturbations produce two distinct density distributions. On the contrary for the negative perturbations it is the steep and not the shallow perturbations that result in separation of baryonic and dark matter components. The second part of the research focuses on the segregation of different types of baryons in elliptical galaxies and clusters of galaxies. Compared with the previous calculations we find that diffusion of some elements is faster by up to an order of magnitude. Also we find that diffusion steepens the baryon distribution, increases the total X-ray luminosity, and changes the stellar spectrum. In the third part, we derive a new limit on the magnetic field production due to electron-ion segregation caused by radiation pressure. In the last part we calculate the upper limit on the short-range interaction between dark matter particles and. Our limit is stricter almost by two orders of magnitude than the previous limit.