Baryogenesis and Dark Matter: Cosmic Origins

This lecture covers the concepts of baryogenesis and dark matter, focusing on their roles in the universe's evolution. It begins with a recap of deuterium abundance and baryon-to-photon ratios, emphasizing the significance of Big Bang nucleosynthesis (BBN) in producing elements like hydrogen and helium. The instructor explains the processes involved in nucleosynthesis, including the formation of deuterium and helium-4, and discusses the conditions necessary for baryogenesis, which is the generation of baryons in the universe. The lecture highlights the importance of baryon number violation and the departure from thermal equilibrium as essential conditions for baryogenesis. The discussion then shifts to dark matter, outlining the evidence for its existence and the ongoing search for its constituents. The instructor emphasizes the need for further research to understand these phenomena, as many questions remain unanswered regarding the origins of baryons and the nature of dark matter.