I donÃ‚Â´t want to derail this thread, because it really doesnÃ‚Â´t add to the discussion here, but this simplified view with absorption and reemission is often told as an explanation for the slower speed of light in matter, even in school and sometimes even in university, because its easy to understand and sufficient for a basic understanding.
If there is a different 'accepted' model/theory then cite it.
Think about it: the discrete energy levels of the electrons in the atom need discrete wavelengths of the absorbed photon. Therefore only a few discrete wavelengths are absorbed and reemitted. Only these would be slowed down if this explanation would be correct.
Actually the atoms where the quantum energy shift matches exactly that of the energy of the photon will be absorbed and not reemitted...this attenuation shows up as a black band of absorbtion in the spectrum.
This is why it is called the 'absorbtion spectrum'.
The speed of light in a medium is wavelength dependant but not for discrete wavelengths but continuously over the whole spectrum.
Where there is 'any' refraction/refelection then absorbtion/reemission has taken place.
Atoms that are struck at a particular vector will always release (there may be a statistical component here that I am not aware of...Compton scaterring, Feynman QED averages and such) at a distinct vector based on the wavelength/energy of the photon and the quantum properties of the atom.
Three problems with your explanation:
- Your explanation explains only the slowing down of discrete wavelengths, not all of the spectrum
This is where I must have fallen short in my prior post...
The whole spectrum is handled by absorbtion/emission or absorbtion only...with also the possibility that an average number of photons will make it through the medium on a straight path without encountering any atoms whatsoever.
- photon emission of excited electron states are in all directions not in a particular direction
Photons are reemitted at a specific vector (on average...understanding that there are many things going on of a quantum nature) based on the wavelength/energy of the photon and the quantum energy properties of the atom being struck.
- photon absorption by electron excitation and following deexcitation has always some loss of energy due to heat radiation therefore all transparent materials would have a slight coloured tone not observed in reality.
Heat radiation is electromagnetic radiation which is made up of emitted photons.
Basic as in low-end for the layman, but in fact incorrect.
If what is being taught in basic physics is not correct, then please elaborate on what theory is correct and whether it has been accepted by the mainstream physics community.
I admit fully that I am a layman and I am not currently knowledgable enough to work out most of the math, but rely on simplified examples and illustrations.