Speaker
Ignacy Sawicki
(University of Geneva, Switzerland)
Description
There remains a slight but chronic tension between the latest Planck results and low-redshift observables: power seems to be consistently lacking at late times. I will describe how a simple model of dark energy, which has the same expansion history as LCDM, induces a scale-dependent correction to the growth rate of dark matter, suppressing power small scales. Since observations in the late universe are performed at smaller scales, this brings the early and late universe into better agreement. I will argue that such scale-dependent behaviour is completely generic in models of dynamical dark energy and modified gravity and must be properly accounted for in modelling of theories and observations.