Symmetries of the Early Universe and the Origin of Matter Michael J. Ramsey-Musolf, Senior Research Associate, California Institute of Technology

Uncovering the microphysics of the early universe is an important endeavor lying at the interface of particle physics, nuclear physics, and cosmology. While the symmetries of the Standard Model of particle physics provide an enormously successful basis for understanding the microphysics of the universe in the era after quarks and leptons became massive, they leave open a number of key questions pertaining to earlier times. In this talk, I briefly review these open questions and the corresponding need for additional symmetries beyond those of the Standard Model. I then focus on one of the questions the Standard Model cannot answer: Why is there more visible matter than anti-matter in the universe? I discuss how exquisitely precise, low-energy experiments may provide new clues about the answer to this question, how these experiments will complement what we can learn from high energy collider studies, and how recent theoretical developments are helping us tackle the origin of visible matter problem with greater clarity.