Neutrinos are ghostly particles that interact so rarely they can pass through planets undetected. But, since they are a natural part of any nuclear interaction, they are also present in nature's most cataclysmic events like supernovas. Our lab searches for a process called "neutrinoless double beta decay". If it does occur, it means that neutrinos are their own anti-particles. This is key to figuring out the role that neutrinos play in Standard Model and the development of the Universe.