Repeated absorption and emission of photons provides a physical basis for Huygens' principle, where every point in the path of the light ray is considered a new point source. This "new point source" is the particle that absorbs photons and emits them, along the light ray (wave front).
However, the emission in this case is in the direction perpendicular to the direction of travel of the particle, in either \(\beta=90^o-\theta\) or \(-\beta\), not in all directions perpendicular to a circular wave front.
Pumping position down! Lightly, lightly, lightly!
