Do Photons Cast Shadows?

The video explores whether photons, or light, can cast shadows. Initially, it seems they cannot, as photons are electromagnetic waves that don't interact directly. However, photons can interact indirectly through electrons, gravitational attraction, and high-energy collisions. The video explains these interactions, focusing on photon scattering and the cosmic microwave background radiation, which can block high-energy gamma rays, effectively casting shadows.

What new insight or understanding did you gain from this video?