Sep 16 (Wed), 14:15 in A315
The nature of voids: simulations, theory, and use in cosmology
Cosmic voids are an exciting tool which can potentially be used to test a number of different cosmological scenarios, including structure formation, dark energy and modified gravity. Yet voids are not well understood. I will discuss the general properties of voids in simulations show that they do not match the predictions of the standard theoretical model of voids based on the excursion set formalism. I will discuss the reasons for this discrepancy and argue that it points to the need for simulation-based calibration of void properties for comparison with observation. I discuss the dependence of void properties on those of the galaxies in which they are found, and identify some universal properties which are independent of these details. In particular I will focus on how voids trace maxima of the gravitational potential field, and the implications of this for lensing and ISW studies.