Explore the Calderon problem and its developments over the past 40 years in this insightful seminar presented by Gunther Uhlmann from the University of Washington and Hong Kong University of Science and Technology. Delve into the fundamental question of determining a medium's conductivity through voltage and current measurements at its boundary, a problem with significant applications in medical imaging and geophysics. Gain an understanding of the progress made since Calderon's initial proposal, including recent advancements in nonlinear equations and nonlocal operators. Discover open problems in the field and broaden your knowledge of partial differential equations and their practical applications.