Seeing cosmic nanostructure: from Plasma to Dark Matter

Niayesh Afshordi (PI / University of Waterloo)

June 25, 2018

–

Abstract: Nonlinear structures are ubiquitous in our universe. They are observed in both baryons and dark matter on megaparsec down to tens of kiloparsec scales, but should extend down to miliparsec scales (and possibly beyond) in standard models of structure formation. I will present the theoretical and observational status of this cosmic nanostructure on miliparsec scales. For baryons, these structures form in cooling flows, which leads to the classical ”cooling flow problem”. I present an improved ”cooling+heating flow” model based on MHD turbulent heating, which solves the problem, explaining the X-ray spectra and stellar budgets of galaxy cluster cores with the Shankura-Sunyaev viscosity parameter \alpha = 0.08. For dark matter, these structures are fundamental predictions of CDM paradigm. I argue that we are on the verge of detecting them (or ruling them out) using the light curves of strongly lensed quasars.