Talk:Spatial Doppler effect
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This article is idiotic, and it purely intended to promote the crackpot POV of Eric Baird. Please note that, according to Wikipedia policy, it is not the obligation of editors to explain to the satisfaction of a crackpot why his crackpot ideas are wrong. The criterion for suitability of Wikipedia articles is that the content is verifiable from reputable published sources. Erk's articles are not verifiable from reputable published sources. They are classic examples of what the Wikipedia founder euphemistically called "original research". Erk is simply promoting his own crackpot views in these articles. In my opinion, they should be deleted.63.24.49.152 22:51, 8 October 2005 (UTC)
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- Someone has just put up a "cleanup-expand" notice, but that misses the whole point. This is a totally bogus topic. It does not need to be expanded, it needs to be deleted.63.24.49.152 22:53, 8 October 2005 (UTC)
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[edit] References
Ryan: your request for additional supporting references was entirely correct. I should have included a references section, and for forgetting to do that, I apologise, I'll do it shortly.
[edit] Response to comments from anonymous poster re: deletion
I think that the comments from anonymous 63.24.49.152 seem to reveal a lack of knowledge of the progress made with special relativity over the last fifty years. SR's predictions for the apparent visible lengths of objects underwent a major overhaul in the early 1960s, with James Terrell and Roger Penrose independently publishing pieces in 1959 saying that previous mainstream statements about visible Lorentz effects under SR had been based on a misinterpretation of the theory. This news triggered a small flood of papers on the subject, mostly in the American Journal of Physics, exploring anew what special relativity's physical predictions really were. After reviewing the math, it was agreed that under SR receding objects appear shortened and approaching objects appear lengthened, and that while the degree of length change under SR departed from earlier predictions by a Lorentz factor, the overall pattern that appeared in earlier theories (recession=shorter, approach=longer) still applied. The apparent visible change in depth for a receding or approaching object is given by the same equation as the apparent change in frequency, just as with the simple propagation-based calculations. SR's matching Lorentz contraction and Lorentz redshift (or matching expansion and blueshift, when using a different frame), preserved this more general relationship.
The defining phrase here, "the spatial analogue of the Doppler effect", is not a piece of "crackpot jargon" invented by me, it comes from McGill (1968). The subject of the correct "visible" predictions of special relativity for approaching and receding objects, and how they are often misunderstood, has now been examined and discussed ad nauseam in popular articles on superluminal jets (the so-called "fingers of god" effect). Math for the corresponding effects under older theory ... well, if you did introductory physics, you should probably have dealt with this subject in high school, its just a function of how far an object moves while the signals from different parts of its structure are in flight.
On SR's visible predictions being the geometric mean of the fixed-observer and fixed-emitter Doppler calculations, well, that should have been pretty obvious from the equations provided. If someone can't cope with visualising how those two equations, multiplied together and with a square root symbol added, gives the third equation, then the the "root product" relationship is explicitly documented (for Doppler effects) in a short peer-reviewed paper by Kalotas and Lee in Am.J.Phys. 58, 187-188 (1990). Some people might not recognise the third equation as relating to the frequency predictions of special relativity, since modern texts don't tend to use this form: I'd refer those readers to Einstein's 1905 electrodynamics paper where this is the sort of format Einstein used when writing down the relativistic Doppler effect. I've tried to cover the issue of the different ways these equations can be written in the separate article article Doppler equations, which I see another anonymous poster (perhaps the same one, who knows) also objects to.
I also notice that 63.24.49.152 previously vandalised this article and replaced the whole thing with just the sentence:
"The term "spatial Doppler effect" is another invention of Eric Baird (a well-known internet physics crackpot) in his on-going efforts to jargonize his misunderstandings of basic physics. It has no other significance."
, my thanks to the person who reverted the article.
While the content may be unfamiliar to some people, its really just bringing together a collection of information from different sources that isn't normally found on a single page, with some worked examples to illustrate. It's a useful concept, it's referred to in print, it works, its simple, and it provides right answers quickly. What more could you want? References to follow, hopefully within a day or so. ErkDemon 22:26, 9 October 2005 (UTC)
[edit] Why Eric Baird's Essays Violate Wikipedia Policy
Eric, everything you've writen in defense of your essays simply proves that they ought to be deleted. The fact that someone, in an article in 1968, said that something was the spatial ANALOGE of the Doppler effect does not mean that there is an accepted physical phenomenon called "The Spatial Doppler Effect". Look, Eric, here is Wikipedia policy. Please read it, and cease violating it:
Quote of Official Wikipedia Policy:
The phrase "original research" in this context refers to ... any new interpretation, analysis, or synthesis of published data, statements, concepts or ideas that, in the words of Wikipedia's founder Jimbo Wales, would amount to a "novel narrative or historical interpretation".
End Quote
Eric, all your Wikipedia articles are "novel narratives and historical interpretations". Taking someone's off-hand comment about an analogy, and treating it a separate physical phenomena, when it is nothing but a straight-forward consequence of known physical phenomena, is your own personal POV. Look, here is another quote of Wikipedia policy:
Quote
Wikipedia's founder, Jimbo Wales, has described original research as follows: The phrase "original research" originated primarily as a practical means to deal with physics cranks, of which of course there are a number on the Web. The basic concept is as follows: It can be quite difficult for us to make any valid judgment as to whether a particular thing is true or not. It isn't appropriate for us to try to determine whether someone's novel theory of physics is valid; we aren't really equipped to do that. But what we can do is check whether or not it actually has been published in reputable journals or by reputable publishers. So it's quite convenient to avoid judging the credibility of things by simply sticking to things that have been judged credible by people much better equipped to decide. The exact same principle will hold true for history" (WikiEN-l, December 3, 2004).
If a viewpoint is held by an extremely small (or vastly limited) minority, it doesn't belong in Wikipedia ... regardless of whether it's true or not; and regardless of whether you can prove it or not.
End quote
Eric, do you understand that these policies were designed SPECIFICALLY to keep people like you from putting your essays into Wikipedia? Do you understand that you are voilating Wikipedia policy when you post essays that represent your own personal "synthesis"? Will you please stop violating these policies?
[edit] Better lemma
If I get this right, this article is about a valid topic, but the lemma choosen is rather uncommon.
If I don't misread article, it should be merged with the short relativistic aberration article.
Since some years there a raytracing packages in use, that generate nice simulations of special and general relativistic effects, see for example the site http://www.spacetimetravel.org/ (translation into English still incomplete), where there are education images and movies like this.
Corvin Zahn workint at this project contributes to the german Wikipedia as de:Benutzer:CorvinZahn, he most likely can donate some stuff for illustration (as he already did with Image:Neutronstar Light Deflection.png).
Pjacobi 17:55, 12 October 2005 (UTC)
[edit] Article name change?
If "spatial Doppler effect" is upsetting some people as a title because it may be mistaken for an existing technical term, then would "Spatial equivalent of the Doppler effect" be a more acceptable header? I think that should probably solve the objection against neologisms, it's too lengthy and explicitly descriptive to be mistaken for an "official" technical term. I originally thought that the three-word contraction was more elegant, but I understand that the anonymous poster or posters seem to think that this is evidence of some evil criminal masterplan! :) ErkDemon 02:53, 17 October 2005 (UTC)
- Did you see my comment 2cm above this one? Why shouldn't we merge to Relativistic aberration? And perhaps even merge something from Relativistic beaming The site http://www.fourmilab.ch/cship/aberration.html also uses "relativistic aberration". Also Corvin and Ute on their site http://www.spacetimetravel.org/ and in American Journal of Physics 68, 56 - 60, 2000. (BTW: the wheel movies are also very cool http://www.spacetimetravel.org/rad/radi_w_0.93.mpg ) --Pjacobi 07:54, 17 October 2005 (UTC)
