Bumps, wiggles, and vibrations: hints of dark matter in our Galaxy

The nature of dark matter remains one of the most pressing questions in physics, driving searches across a vast range of scales - from microscopic interactions of individual particles to macroscopic gravitational effects on the cosmos. In this talk, I will explore two exciting avenues for probing dark matter: direct interactions with materials and its influence on stellar streams. At sub-GeV masses, traditional direct detection methods become ineffective, requiring new approaches that exploit the material properties of detector crystals to observe nuclear recoils and phonon excitations. Meanwhile, in the Milky Way, stellar streams serve as cosmic detectors, offering a unique way to probe the presence of low-mass dark matter subhalos through perturbations in their structure. I will discuss recent developments in both of these frontiers, highlighting how they can contribute to our ongoing search for the subtle signatures of dark matter.

Speaker: Tongyan Lin, UC San Diego

This seminar was originally scheduled for February 17, 2025.