Explore a comprehensive lecture on sequential equilibria in infinite extensive form games presented by Michael Greinecker at the One World Mathematical Game Theory Seminar. Delve into the complexities of games with uncountable action spaces, focusing on multistage games and the challenges posed by informational discontinuities. Learn about the characterization of sequential equilibrium strategy profiles, the importance of continuous signal functions, and the concept of strategic measures. Examine how probability zero events impact game dynamics and why sequential rationality is tested only at observable events. Gain insights into the limitations of completely mixed strategies and the alternative approach of using strategic measures that reach all observable events.