Partially Acoustic Dark Matter, Interacting Dark Radiation, and Large Scale Structure
The standard paradigm of collisionless cold dark matter is in tension with measurements on large scales. In particular, the best fit values of the Hubble rate and the matter density perturbation inferred from the CMB seem inconsistent with the results from direct measurements. In this talk, I will discuss these issues and propose a solution to both problems from a dark sector that contains dark acoustic oscillations with dark fluid. Such a solution can be tested by future experiments designed to probe the CMB and large scale structure.