High-Frequency Approximation in Gravitational Lensing and Wave Optics

Learn about the intersection of geometric optics and gravitational lensing in this 30-minute physics lecture from the Workshop on "Lensing and Wave Optics in Strong Gravity" at the Erwin Schrödinger International Institute. Explore how combining geometric optics with field-centered perspectives using Green functions for Maxwell's equations and linearized Einstein equations yields new insights into optical foundations. Discover why geometric-optics ansatz emerges differently across various physical scenarios, understand the absence of tails in high-frequency approximations, and examine the relationships between field and source properties. Investigate the invariant quantities under geometrical transformations while gaining a deeper understanding of how different approaches to gravitational lensing complement and enhance our comprehension of optical phenomena in strong gravity environments.