Halo bias in the excursion set approach

فرنیک نیک اختر

Department of Physics and Astronomy at the University of Pennsylvania

Abstract: Nonlinear structure formation is an important area in the modern cosmology, where deep questions can be addressed by large-scale structure data, especially the questions which are related to the dark universe – the physics of dark matter and dark energy. In this arena, the abundance and clustering of dark matter halos probe important features of the standard model of cosmology. The excursion set approach is a framework for estimating how the statistical properties of nonlinear structures in the cosmos depend on the history of the universe and the nature of gravity. In this theory, one associates a random walk with each position in the initial density field, and the barrier to be crossed is determined by the collapse model. The main problem here is the first passage time problem and the first up-crossing distribution is the quantity which is related to the abundance of nonlinear objects. My recent work is about approximations of the first up-crossing distribution (for non-Markovian walks) and modeling the abundance of halos, and in this talk, I would like to show the associated implications for halo bias.

یکشنبه 9 دی 1397، ساعت 15:00

دانشکده فیزیک، طبقه اول کلاس فیزیک 3