Explore the fundamental concepts of axion electrodynamics in this comprehensive lecture delivered by Alexander Millar at the Galileo Galilei Institute. Delve into the intricacies of axion theory, examining its principles and applications in modern physics. Gain insights into the latest developments in this field and understand how axion electrodynamics contributes to our understanding of particle physics and cosmology. Over the course of 1 hour and 20 minutes, engage with complex theoretical frameworks and cutting-edge research presented by an expert in the field.