Anthony Aguirre is a Professor of Physics at University of California at Santa Cruz, member of the Santa Cruz Institute for Particle Physics, and Associate Director of the Foundational Questions Institute.  Prior to UCSC, he received his PhD from Harvard University, and was a member at the Institute for Advanced Study. Aguirre has worked on a wide variety of topics in theoretical cosmology, including galaxy formation and evolution, black holes and gravity physics, the the foundationals of quantum mechanics, the arrow of time, and inflationary cosmology.  Recently he has been most occupied with the meaning, structure, and testability of the inflationary ‘multiverse’.