Testing Gravity with Astrophysics
Jeremy Sakstein
University of Pennsylvania

Some of the key unsolved mysteries in modern physics involve gravity, yet we have only tested our theories in the solar system and using a few select extra-solar objects. This will change in the next decade as a wealth of precision data will become available on astrophysical and cosmological scales. For the first time we will look at the Universe both electromagnetically, and using gravitational waves. In this talk I will discuss how this presents us with the unprecedented opportunity to test the nature of gravity on scales where there are already anomalies in the data. Through a continued interdisciplinary effort connecting cosmology to astrophysical objects and gravitational waves we can make new discoveries to understand why the Universe is accelerating (dark energy), and how gravity behaves at large distances. I will present several examples of how developing novel probes has already been successful, and how the next decade of data-driven cosmology and astrophysics will maximize the discovery potential of this program.