The Force of the Dark Side Neal Weiner, Associate Professor of Physics, New York University

While evidence for the existence of dark matter has grown over the past two decades, information on what it actually is remains elusive. Conventional ideas have been limited to a single, essentially non interacting particle to make up the majority of the matter of the universe. Of late, a series of results from astrophysics and direct detection experiments have prompted an explosion of new ideas for dark matter, including new forces, excited states, and light WIMPs. I will review what has prompted these new ideas, and why they have changed how we think about other signatures of dark matter, such as would show up at colliders. Finally, I will discuss what experiments in the near future will clarify these questions, and let us know if we have finally begun to probe the dynamics of the dark sector.