Hello, Ok, so I’ve been searching about this for a while and there seems to be a difference in explanations that confuses me. What concerns me is the exact detailed physical mechanism that makes particles cause a scatter of a photon and an emission of a photon. The Wiki page about scattering says the following about one type of scattering, Rayleigh Scattering: “The particles may be individual atoms or molecules. It can occur when light travels through transparent solids and liquids, but is most prominently seen in gases. Rayleigh scattering results from the electric polarizability of the particles. The oscillating electric field of a light wave acts on the charges within a particle, causing them to move at the same frequency. The particle therefore becomes a small radiating dipole whose radiation we see as scattered light.” To me, this explanation seems to be the same as when a particle meets a photon that has the same energy/frequency as a potential energy/frequency state of the particle, with the result of the particle absorbing this photon and emitting it again. This is the description found here: http://hyperphysics.phy-astr.gsu.edu/hbase/mod3.html#c3 However, several sources say that that absorption and emission is different from scattering. My question is then, in what way exactly? I am aware that, for example, Rayleigh scattering is elastic which means that the photon that left the particle has the same energy level as the one that hit the particle, but what happened exactly in between? Did it get absorbed and emitted in the same energy quantity? Here’s a good discussion about the difference between emission (fluorescence) and Raman scattering: http://physics.stackexchange.com/questions/38459/what-is-the-difference-between-raman-scattering-and-fluorescence There seems to be 2 different opinions on this in that discussion: 1. That they’re the same in the sense of the photon being absorbed and then emitted again, with the only difference being the time between absorption and emission if you compare fluorescence with Raman scattering. So there is a time in which the particle is being excited by the photon. 2. That, in the case of Raman scattering, there is no absorption of the photon but a partial interaction of the photon with the particle which results in the particle taking a bit of energy away from the photon.So there is no excitation of the particle whatsoever by the photon. Point 2 bothers me because I’m taught that a photon cannot be partially absorbed or interacted with, since it’s a discrete energy state. So what is it exactly that separates the mechanism of emission from scattering? Preferably comparing it with every type of scattering.