Talk:Precursor (physics)

claim about speed of high frequencies

There is an attempt to explain the reason why the precursors exhibit such frequencies. For example, the Sommerfeld (early) shows really high frequencies, much bigger than the incident light. It is not true neither accurate to try to explain this using the speed at which high frequencies travel in mediums with normal dispersion. Brillouin even claims "If we let white light fall perpendicularly on a dispersive plate, then the less refracted (and hence ‘faster’) components of the white light do not precede the more refracted (and hence ‘slower’) components, and the light is not red at the first instance of emergence. Instead, the wave front of each component propagates with the same velocity c through the plate, and each component contributes equally to the energy of the initially emerging light. These initially emerging forerunners do not show the colors of the components of which they are composed; instead, they have an ultraviolet wavelength determined by the dispersive power and thickness of the plate, and a very small intensity." If the explanation was that, then red frequencies should come first. Goeppert (talk) 21:08, 7 August 2024 (UTC)