Talk:Scattering
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An explanation for the inexperienced as to what direct and reverse paths are would help - Anon== Missing scattering articles ==
Another encyclopedia has articles on these forms of scattering, perhaps Wikipedia should have some of them. Some may be too obscure or just alternative names. Some could probably be worked into existing articles, as well. Don't forget to create a redirect, if you do that.
- coherent scattering
- bhabha scattering
- gravitational scattering
- incoherent scattering
- inelastic neutron scattering
- møller scattering
- multiple scattering
- scattering coefficient
- scattering polarization
- single scattering
- single scattering albedo
Holy sh*t this article is a mess ... is there a macro to mark it thus? gbrandt 19:57, 3 April 2006 (UTC)
It does exhibit a very parochial (and perhaps almost scattered) outlook. I see this a lot in Wikipedia articles, a couple people talk about their niches but nobody ties it together generally. I'm working on a more general overview that explains what scattering is before we go into what scattering is in 2 or 3 specific systems. I think we need that more than we need an article on gravitational scattering, though there's nothing wrong with that if somebody's dying to write one. :). Tarchon 00:40, 5 April 2006 (UTC)
Table comparison of scattering phenomena
editA table in this article to compare/contrast different scattering processes and the names assigned to them would be a huge improvement. Flying Jazz 13:14, 21 December 2005 (UTC)
elasticity of Brillouin scattering
editI put Brillouin under elastic because the energy change (from one viewpoint) is a Doppler shift due to the velocity of a propagating acoustic wave - as I noted, the distinction between elastic and inelastic is somewhat arbitrary, since to be totally exact, there really is no such thing as a completely inelastic interaction. Even Rayleigh and Mie scattering typically involve some sort of measureable shift or broadening, which is commonly used in LIDAR and radar. Whether you label something elastic or inelastic just depends on how closely you're looking at it. It is true that "generally the whole point of measuring a Brillouin spectrum in physics is to measure the energy change" but not all Brillouin scattering is about phonon spectroscopy. By far the most common application of Brillouin is in AOMs, in which case the energy change may or may not be considered significant. It depends on whether you're using it as an intensity modulator or frequency modulator. Someone who does Doppler weather LIDAR could just as well argue that Rayleigh scattering is inelastic because, indeed, they are measuring an energy shift, but that's not even close to being the most common context in which Rayleigh scattering is encountered. It's fine with me if it's put under "inelastic" because I can see it either way (and certainly phonon spectroscopy people sometimes use the term), but it's not as cut and dried as the anonymous commentator from "Blaze Labs" makes it out to be. Tarchon 20:49, 20 May 2006 (UTC)
Sound? Radiation?
editSound is not radiation...I corrected the sentence. (anonymous comment)
- I have to disagree - sound is very much a type of radiation. In physics, a wave is a wave. If every one of the 100 different niches of physics that involve scattering gets its own little "scattering is also the deflection [insert form of radiation]", you end up with a pretty unwieldy article.
- If you don't believe me that "radiation" is a general term including sound, just google "acoustic radiation."
- http://www.du.edu/~jcalvert/waves/radiate.htm
- http://www.sfu.ca/sonic-studio/handbook/Acoustic_Radiation.html
- http://scienceworld.wolfram.com/physics/AcousticRadiation.html
- Even other Wikipedia articles consider sound to be a form of radiation, e.g. Acoustic_radiation_pressure
- I will "uncorrect" if unrebutted.
- Tarchon 23:10, 20 February 2007 (UTC)
Color depends on Frequency, not wavelength
editThe color of a monochromatic lightray depends on the frequency not the wavelength, So when you write: "α≈1: Mie scattering (particle about the same size as wavelength of light)" It shoud be " particle about the same size as the wavelength of a lightray in vacuum" Because the wavelength could drastically shorten when it goes into a much denser medium. (Robrecht) —Preceding unsigned comment added by 82.36.237.108 (talk) 12:04, 5 April 2011 (UTC)
Both the title and the reasoning are incorrect, in my opinion. The relevant parameter is the dimensionless ratio of the particle size to the wavelength of light in the medium in which the particle is embedded. The wavelength of the light in vacuum is not the appropriate parameter. To be anthropomorphic, the particle does not "know" what wavelength the light would if it were in a vacuum. AlanParkerFrance (talk) 08:07, 9 January 2013 (UTC)
Light scattering
editEditors of this article might be interested in the new article Light scattering.--Srleffler (talk) 16:52, 27 July 2009 (UTC)
Correct?
editdeviate from a straight trajectory by one or more localized non-uniformities in the medium through which they pass, is this true for Rayleigh scattering? I don't think so. --Gerrit CUTEDH 08:48, 14 October 2011 (UTC)
- How is it not true for Rayleigh scattering? Tarchon (talk) 00:36, 10 November 2012 (UTC)
Single and multiple scattering
editThis section is terrible, in my opinion. The distinction is due to the concentration of scattering centers, not their proximity. In single scattering, the incoming radiation is only scattered once, by one scatterer, before reaching the detector. As the concentration of scatterers increases, the number of scattering events that is single decreases. Multiple scattering is like a random walk. It causes a significant loss of information compared with single scattering. As fog gets thicker, the detail is washed out. To be continued...
AlanParkerFrance (talk) 19:24, 3 February 2013 (UTC)
"The main difference between the effects of single and multiple scattering is that single scattering can usually be treated as a random phenomenon and multiple scattering is usually more stochastic."
"...random....more stochastic". This sentence lacks a clear meaning. — Preceding unsigned comment added by 80.223.85.137 (talk) 18:13, 13 November 2013 (UTC)
- Completely agree with this. In my vocabulary "stochastic" means "made by a random process". What is the difference between that and a random phenomenon? Chaleur (talk) 17:57, 28 February 2014 (UTC)
I originally wrote a lot of it, but someone came in and chanced "deterministic" to "stochastic" as well as some of the other wording. I swear, it originally made sense before Wikipedia entropy got to it. 68.15.76.10 (talk) 00:14, 20 May 2017 (UTC)
Scattering Theory
editQUOTE: More precisely, scattering consists of the study of how solutions of partial differential equations, propagating freely "in the distant past", come together and interact with one another or with a boundary condition, and then propagate away "to the distant future". UNQUOTE -- This claim: that "how ...solutions...come together and interact [and]... propagate away" is at best misleading, I call it wrong. Solutions don't propagate, they don't come together and they don't interact. To confound the description of the thing (the equations) with the thing (the waves) is a naïve mistake. I will leave the silliness about them (the solutions) existing in the distant past for others to ridicule.173.189.79.119 (talk) 23:30, 23 April 2013 (UTC)
coherent scattering
editHi, coherent scattering redirects here but thre is no mention of this term within this article. Could you create an article to describe this term, or at least add some words into this article? Thanks in advance. Pamputt (talk) 20:21, 27 October 2017 (UTC)
Light Scattering is mainly a single event effect
editThe Scattered light is considered in the literature as a diffusive light, light that passed a number of scattering events before it left the scattering material. Diffusely scattered light must obey Lambert's Cosine scattering law. In the case of unidirectional light scattered backward from a surface of a sphere, the meaning is maximum scattering intensity in the middle of the sphere surface, and a decline to zero toward the periphery by the cosine law. The full moon looks uniform and people continue to assume that the light is diffusely scattered from it. More than that. The nearly uniform sphere image is common to all the planets and their moons, including the earth as observed from the moon. Out of thousands upon thousands of true photos, there is no single true photo that obeys Lambert's Cosine law. The only photos that do obey the law are rendered photos, photos that are at least partly simulated. Contrary to all that, if the scattering is assumed to be mainly a single event, then all the scattering dipoles are directly stimulated by the light radiation on the illuminated scattering material. Then scattering by them must be coherent, and then the full moon and all the other illuminated bodies, with similar illumination geometry, must be uniform, at least approximately. The full moon tells us that single event scattering is dominant. Maybe with small corrections of multiple scattering. Why is the single event dominant? It seems that the effect is geometrical and statistical. If we consider one event scattering, two event scattering, multiple event scattering, then the event probability will decline with an increasing number of scatterings. The single event has a probability of at least 50% and it is the strongest event. Nearly all the background that surrounds us is a singly scattered light. A true diffusely scattered light is rather rare.
Urila (talk) 03:25, 13 May 2020 (UTC)urila
Scattering
editThe first line in the article: "Atoms or molecules which are exposed to light absorb light energy and re-emit light in different directions with different intensity." Transparent materials do not absorb light and do not re-emit light. Yet, they do scatter light. Absorption and Re-emission of light are photo-emission. Urila (talk) 09:06, 10 October 2020 (UTC)
- Yes, it's a weird thing to say and not physically correct, so I removed it. 70.181.67.17 (talk) 04:00, 25 October 2020 (UTC)
Help me
editCan anyone help me to understand these sentences?
- 1)A well-controlled laser beam can be exactly positioned to scatter off a microscopic particle with a deterministic outcome.
In these two sentences I can't understand the relation of relative to with the sentences. Can anyone help me with alternatives?
- 2)Because the location of a single scattering center is not usually well known relative to the path of the radiation, the outcome, which tends to depend strongly on the exact incoming trajectory, appears random to an observer.
- 3) In this case, the atom's exact position relative to the path of the electron is unknown and would be unmeasurable.
- 4) Prosaically, wave scattering corresponds to the collision and scattering of a wave with some material object.
Nakul ( talk ) — Preceding undated comment added 09:44, 10 October 2021 (UTC)
Merging from article Scattering theory
editThat article has a lot a similar content, though this article give broader explanations, it 's probably better if these articles are merged —CrafterNova [ TALK ] [ CONT ] 15:43, 5 February 2022 (UTC)
- Support both articles are clearly about the same topic, we should not hide more precise content under different names.--ReyHahn (talk) 15:39, 16 March 2022 (UTC)
- I support the merging of the 2 articles, but propose "Scattering Theory" (not merely "Scattering") as the common title. Lawrence Normie (talk) 14:43, 9 June 2022 (UTC)
- Support the merge as proposed, using Scattering as the target - it's the broader title, and use the contents include practical, empirical and qualitative descriptions, meaning that theory won't cover all aspects of the merged page. Klbrain (talk) 20:52, 24 August 2022 (UTC)
- Merger complete. Klbrain (talk) 10:38, 27 December 2022 (UTC)
- Support the merge as proposed, using Scattering as the target - it's the broader title, and use the contents include practical, empirical and qualitative descriptions, meaning that theory won't cover all aspects of the merged page. Klbrain (talk) 20:52, 24 August 2022 (UTC)
Scattering experiments
editScattering experiments are very important in particle physics and have a long history. Yet we don't have much in Wikipedia that covers the experimental side. There once was a very brief section here that described the physics of doing scattering experiments, to which a long broken anchor in another article is trying to link. There should be a least an introduction here. In its absence is there any other article in Wikipedia that covers this? StarryGrandma (talk) 19:34, 27 December 2022 (UTC)