Abstract:

Over the past decade, a variety of observations have solidified the evidence for an accelerating Universe. In the next decade, larger surveys will attempt to pinpoint the physical explanation for cosmic acceleration by increasing the precision of established methods and enabling new techniques to test models of dark energy and modified gravity. I will review the main observational tools available for investigating cosmic acceleration, using both recent results from surveys such as BOSS and forecasts for proposed surveys to demonstrate the complementarity between probes including Type Ia supernovae, baryon acoustic oscillations, and weak lensing. I will show how these forecasts can be used to study the sensitivity of predicted constraints on dark energy and modified gravity parameters to survey properties and theoretical assumptions, providing guidance for optimizing observational strategies. An unambiguous and robust explanation for the accelerating Universe can only be obtained by a program that combines and advances several probes of the expansion history and the growth of large-scale structure.