Rotational velocities in large scale structure.

摘要

In perturbation theory studies of the large-scale structure of the universe, it is common procedure to ignore the effects of an initial rotational velocity field. This has been justified by the fact that in the linear regime, rotational velocities decay with the expansion of the universe, a simple result of conservation of angular momentum. In this dissertation, we explore the consequences of retaining this mode, based on the assumption that gravitational collapse should lead to the return of appreciable rotational velocities. We extend the classical perturbation theory to include rotational modes up to the quasi-linear third order and find that these modes contribute in a non-trivial manner. We then include these modes in the non-linear regime, incorporating them into the halo model. We study a specific application of non-linear collapse, the calculation of the kinetic Sunyaev-Zeldovich effect, with the inclusion of rotational velocity modes. We find that these modes do not contribute significantly at any angular scale available to modern observation.