This is true, but Huygens is a general principle as well.
My understanding of the Huygens-Fresnel is that it describes, e.g., how light appears as plane waves and then why it becomes spherical when…
This is true, but Huygens is a general principle as well.
My understanding of the Huygens-Fresnel is that it describes, e.g., how light appears as plane waves and then why it becomes spherical when it passes through a hole.
So, for example, when you hit a reflective surface with a plane wave and it bounces off (as with a mirror). Each point on the reflective surface behaves like an emitter of a spherical wave. But, cancellations between the off-angle waves produces a plane wave.
Turns out that Huygens isn't correct for optics though it is for Schrodinger's.
The main thing you notice is that when you look at converting from path integrals back to Schrodinger's, Huygen's pops out of the equations. Feynman noted that in his thesis in 1948.
This is a good presentation on the two: http://www1.phys.vt.edu/~takeuchi/Tools/CSAAPT-Spring2019-Huygens&Feynman.pdf