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## No evidence for length contraction

I hope this is the appropriate place for this request for clarification of the guidelines for inclusion of non-mainstream articles/papers on the length contraction aspect of SR. (I put in a similar request in the general "request for comments" section yesterday, but that section is not specific to relativity, so may be overlooked by SR physicists, and there have been no comments yet.) I find a general consensus that there is no direct empirical evidence for physical length contraction or contraction of the distance between objects in space. Yet this consensus is not allowed so much as a mention in the "Length contraction" section of relativity. Specifically the usual argument from "time dilation for muons" does not physically require a shorter distance traveled, as a slower rate of decay (at higher velocity) allows for an extended range of travel. Further, all cases of theoretical "physical length contraction" are (theoretical) observer/frame dependent measurement variations, which do not require physical contraction of objects or distances. Disambiguation is required to distinguish between changes in the 4-D "spacetime" *model* (as virtually viewed from different frames) and changes in physical objects themselves (and the distances between them.) Comments, please. LCcritic (talk) 20:00, 9 November 2013 (UTC)

Please see Tests of special relativity#Time dilation and Length contraction and Test theories of special relativity. JRSpriggs (talk) 22:00, 9 November 2013 (UTC)
- DVdm (talk) 10:45, 10 November 2013 (UTC)

## Criticism of relativity not allowed

The whole section on Criticism of Relativity is a sham created by restrictive Wiki editorial policy because no substantive criticism is allowed.

Conclusion of the section's opening statements: “Even today there are some critics of relativity (sometimes called "anti-relativists"); however, their viewpoints are not taken seriously by the scientific community.” In other words, no criticism of relativity is to be “taken seriously by the scientific community.” So, according to the Wiki editor who wrote that, the whole section on criticism of relativity should just end there and dismiss all criticism.

Opening statement in the Philosophical Criticism sub-section: “The consequences of relativity, such as the change of ordinary concepts of space and time, as well as the introduction of non-Euclidean geometry in general relativity, were criticized by some philosophers of different philosophical schools. It was characteristic for many philosophical critics, that they had insufficient knowledge of the mathematical and formal basis of relativity, consequently the criticisms often missed the heart of the matter.”

In other words, philosophy is irrelevant to the math and physics of relativity. Philosophers are “not to be taken seriously." The Philosophical Criticism section should end there, though that sub-section would already be precluded by the opening section. Even the most fundamental philosophical criticism, “at the very heart of the matter” is “not allowed,” i.e., that Einstein’s philosophy was that there is *no real world,* that it all depends on differences in observation. So the obvious argument that, for instance, Earth’s diameter does not change with how it might be observed (i.e., there is in fact a "real world/Earth") is “not allowed.”

Since no critic of relativity can get credentialed in the field, all such critics are considered “cranks from the fringe,” ("Catch 22") so references to these critics (and there are many) are “not allowed.” The result in summary is that those who criticize relativity are not credialed references, so their criticisms are “not allowed.” Will this task force on relativity please reconsider the basic editorial policy on what “is allowed” as criticism? Thanks. Ps: I hope DVdm is "not allowed" to censor this on any number of technicalities, like "forum shopping" just because there is no place "allowed" in this encyclopedia for legitimate criticism of relativity (i.e., that there is no such thing as legitimate criticism of relativity.) LCcritic (talk) 19:33, 20 November 2013 (UTC)

Note - see our chat at Talk:Criticism of the theory of relativity#Einstein's denial of a "real world" as the basis for SR. - DVdm (talk) 20:00, 20 November 2013 (UTC)
Einstein did not say that there is no real world. That is not the thrust of his theory. What you are saying makes about as much sense as if a flat-Earther were to criticize the (roughly) spherical globe as a denial of the reality of the Earth.
What "relativity" means is that certain relationships which were previously thought to depend on only a few things must now be understood as depending on a few more things as well. For example, when I say that "the table is near", I mean that the table is near to me. In other words, the notion "near" is relative to the observer rather than being absolute. It makes no sense to say that a table is near (or far) without reference to an observer. Similarly, the velocity of an object depends on the observer. And the special theory of relativity tell us that the length of an object also depends on the observer. And the rate at which processes proceed depends on the observer. Why is that so terrible? JRSpriggs (talk) 10:50, 21 November 2013 (UTC)
While there is a case that the problem would fit under "Philosophical criticism", adding it would give it WP:UNDUE weight. Can you find better sources than Lindner and Physics Essays for Einstein's position on realism and comments thereupon? Paradoctor (talk) 12:56, 21 November 2013 (UTC)
First, my 'chat' with with DVdm which he linked above resulted in no changes to the Criticisms of Relativity Wiki text, for all the technical reasons he cited. My suggested additions were stonewalled. Secondly, Einstein DID deny the "real world." Here it is again: He explicitly denied the statement, “The physical world is real.”... "It appears to me that the 'real' is an intrinsically empty, meaningless category... This division is, to be sure, not an arbitrary one, but instead... I concede that the natural sciences concern the 'real,' but *I am still not a realist.*" (my *...* emphasis.) See full text of quote in the linked 'chat' with DVdm above.
Next, Lindler's lack of praises from credentialed relativity theorists disqualifies him from being a 'legitimate critic' only because of the "Catch 22" exclusion policy, which does not allow any substantive criticism of relativity, as I explained above. He is a philosopher with a very basic, very valid criticism, again: "If we accept the theory that *a physical Cosmos exists*, and that **our sensations and measurements result from our interactions with the Cosmos**, then we should not restrict our physics, as Einstein did, to the modeling of our sensations and measurements." (again, my *, ** emphasis.)
Godel's article, via title alone, relates relativity theory to idealistic philosophy, which denies a "real world" independent of changing observations of it. “The Relationship Between Relativity Theory and Idealistic Philosophy.”
Regarding (again) the opening statement in the Philosophical Criticisms sub-section (my * emphasis):
“The consequences of relativity, such as the change of ordinary concepts of space and time, as well as the introduction of non-Euclidean geometry in general relativity, were criticized by some philosophers of different philosophical schools. *It was characteristic for many philosophical critics that they had insufficient knowledge of the mathematical and formal basis of relativity.*”
Here is an example of a philosopher, Kelley Ross, who has a thorough understanding of the transition from Euclidean to non-Euclidean geometry and cosmology yet criticizes many of the *assumptions* required for that transition: http://www.friesian.com/curved-1.htm
Examples: See the section, Curved Space and Non-Euclidean Geometry regarding intrinsic vs extrinsic (imaginary models of) curvature. See also the section on Geometry in Einstein's Theory of Relativity:
“Intrinsic curvature, which was introduced by Riemann to explain how straight lines could have the properties associated with curvature without being curved in the ordinary sense, is now used to explain how something which is obviously curved, e.g. the orbit of a planet, is really straight. Something has gotten turned around.”
Finally, see his Conclusion (same notation for my emphasis):
"Just because the math works doesn't mean that we understand what is happening in nature. *Every physical theory has a mathematical component and a conceptual component, but these two are often confused.* Many speak as though the mathematical component confers understanding,...
Nevertheless, there is often still a kind of deliberate know-nothing-ism that **the mathematics is the explanation. It isn't.** Instead, **each theory contains a conceptual interpretation that assigns meaning to its mathematical expressions.** In non-Euclidean geometry and its :::: application by Einstein, the most important conceptual question is over **the meaning of "curvature" and the ontological status of the dimensions of space, time, (ed: and ‘”spacetime”)**...
Finally, JRspriggs said, "And the special theory of relativity tell us that the length of an object also depends on the observer. And the rate at which processes proceed depends on the observer. Why is that so terrible?" It is "terrible" because the length of Earth's diameter, as a very obvious example of a massive physical object, does not change with the speed and direction of an approaching relativistic observer, as relativity theory insists. It is "terrible" because Earth is a "real" physical object not just a 4D "spacetime model" subject to change with how one looks at it from various speeds and directions. The realism vs idealism philosophical debate is bedrock fundamental to the validity (or not) of an Earth which changes shape... or to the claim that the distances between stars depends on how interstellar travelers might someday measure them from various relativistic speeds and directions of travel. But this philosophical debate is **not allowed!** (Yes, DVdm, this is a "discussion" among editors, and he asked the question.)LCcritic (talk) 21:19, 21 November 2013 (UTC)
The criteria for reliable sources can be found at WP:RS. Can you find anything satisfying these criteria not already in the article? Paradoctor (talk) 22:14, 21 November 2013 (UTC)
Regarding "Lindler's lack of praises from credentialed relativity theorists..." to make Lindler worth mentioning here as legitimate critic: note that wp:secondary sources need not praise the author to make his critisism worth a mention in Wikipedia. We need such credentialed sources to mention (perhaps by praising or even by denouncing—see Dingle) and discuss that author to begin with. Any MD with a hobby can play the critic of anything they weren't properly trained in, but if they are ignored, they have no place here. And that is by this place's very design. If you want to change that, you wil need to change some of the core policies.
Regarding your "length of Earth's diameter as a very obvious example of a massive physical object": that length, as measured by an approaching relativistic observer, does change with the speed and direction of an approaching relativistic observer. Why is that so terrible? The speed, kinetic energy and momentum of a massive physical bullet also depend on who is making the measurements. We don't find that terrible. - DVdm (talk) 22:41, 21 November 2013 (UTC)
My point is that the "criteria for reliable sources" is based on credentials as approved by relativity theorists and that Wiki states specifically (opening the Criticisms section) that no critics of relativity qualify as "reliable sources" in the "scientific community" (of relativity theorists.) The "rules" exclude all philosophical discussion of the most basic issue, relativity's idealism excluding the opposing argument, realism (a world independent of observation.) Realists do not have the 'proper credentials' because they are disregarded by that community as critics of relativity, ergo "cranks" by whatever derogatory label. And around it goes. Realists argue that the changing measurements (of Earth in the above example) from all different frames do not reflect actual physical changes it Earth itself. Idealists, relativity theorists in this case, insist that that Earth does change shapes with variations in how it might be observed from relativistic frames. But that argument is not allowed as "Philosophical Criticism"... because, of course, philosophical realists are not properly credentialed by the community of relativity theorists. Is anyone following this? LCcritic (talk) 03:31, 22 November 2013 (UTC)
"credentials as approved by relativity theorists" Please cite WP:RS where it says that, I can't find it.
"relativity's idealism" Which reliable source says that relativity is an idealist theory?
"Is anyone following this?" You can use "Page information" in the page toolbox. Paradoctor (talk) 04:04, 22 November 2013 (UTC)
Re "relativity theorists in this case, insist that that Earth does change shapes with variations in how it might be observed from relativistic frames": no, for the n-th time, relativity says that the Earth, as measured by other frames, does change shapes with variations in how it might be observed from these frames. You consistently omit that qualifier, and it is essential. - DVdm (talk) 08:04, 22 November 2013 (UTC)
In the Identifying Reliable Sources guidelines:
"This means that we publish the opinions only of reliable authors, and *not the opinions of Wikipedians who have read and interpreted primary source material for themselves.*” (My *)
The opening statement in the Criticisms of Relativity section violate this guideline, as per the final statement in that opening (quoted again for easy reference): "Even today there are some critics of relativity (sometimes called "anti-relativists"); however, their viewpoints are not taken seriously by the scientific community.”
“Wikipedia articles are required to present a neutral point of view.” The whole Criticisms section violates that with the stated opinion quoted above, which prevails throughout the section, i.e., that criticisms of relativity are “not taken seriously." This is an example of the editor, presenting as an expert on relativity, discrediting all critics, i.e., none with "approved credentials, in answer to Paradoctor's challenge. Regarding your challenge: "'relativity's idealism' Which reliable source says that relativity is an idealist theory?" Claiming that there is no real world, that there is no "reality" independent all different varieties of ways to observe the same object (as relativity does) IS idealism. Yet no discussion of that in the Philosophical Criticism subsection is allowed.
DVdm, your "for the n-th time..." condescending, professorial attitude is not productive, nor is it civil, as required by the guidelines. JRspriggs said, "And the special theory of relativity tell us that the length of an object also depends on the observer." That is the prevailing claim.
The Length Contraction section opens with: "In physics, *length contraction is the phenomenon of a decrease in length* measured by an observer of objects which are traveling at any non-zero velocity relative to the observer." (my * emphasis) The phenomenon is said to be a decrease in length of an object. The way that claimed decrease is measured varies, not the object itself, as implied in the structure of the sentence.
The most common example of length contraction is probably the pole/ladder and barn thought experiment. The claim is that a 20 foot pole will fit into a 10 foot barn, *as measured from a given relativistic frame.* However the “as measured from” phrase will not allow the above long pole to fit into the shorter barn. Differences in how objects are observed/measured can not cause differences in the physical objects themselves. Even the claim that the pole's atoms are compacted by high velocity (resulting in shorter physical length) can not possible apply to Earth's diameter with a high velocity relative to an approaching observer.
A typical example from an “ask the physicist” website Q&A (I verified this by asking); Q: "According to relativity theory, what is the length of Earth’s diameter?" A: “It depends on who is observing it.” Clearly this is idealism in denial of realism.
I gave an example of a well credentialed philosopher criticizing the assumptions upon which non-Euclidean geometry/cosmology and relativity are based. This was in direct reply to the claim in the "Philosophical Criticism" subsection (the personal opinion of the editor presenting that section!) that no philosophers understand the transition to non-Euclidean. My example has so far been ignored here, presumably in keeping with the editorial *opinion and policy* here that all critics of relativity are cranks.LCcritic (talk) 20:16, 22 November 2013 (UTC)
LCcritic, while I am still willing to extend the benefit of doubt to you, your behavior is quickly approaching the point where this does not seem warranted to me. WP:INDENT, it's not difficult, and it's part of how we do things around here. If you want an exception, state your case. I'm not linking to policy and guidelines out of boredom.
You criticized the lead of Criticism of the theory of relativity. I took that as a request for this edit. Note that the applicable policy is WP:V, not WP:RS, as the statement is not sourced currently. You could have done this yourself, and nobody would have bat an eyelid. Even deleting the statement with an appropriate edit summary like "unsourced" would have been acceptable.
"This is an example of the editor, presenting as an expert on relativity, discrediting all critics" Please assume good faith. The editor who added this sentence to the article probably thought that it fairly represented the literature. I know I do. You want a source for that, that's entirely apropriate, and you'll get it soon enough, I think.
Update Fast service courtesy of D.H. Paradoctor (talk) 15:15, 23 November 2013 (UTC)
"in answer to Paradoctor's challenge" You didn't answer my request to cite WP:RS where it says "credentials as approved by relativity theorists". Note that WP:RS is about publications, not people. "Credentials" are mentioned only in reference to self-published sources.
"Which reliable source says that relativity is an idealist theory?" That is the question I want you answer, because it is you who is making the claim: "most basic issue, relativity's idealism".
If I was you, I'd rethink accusing DVDm of being incivil. IMHO, he is showing restraint. I've seen experienced Wikipedians react considerably harsher in situations like this. Maybe reading WP:COOL would be a good idea.
"Length Contraction section" There is no such section in Criticism of the theory of relativity. Which article are you talking about?
"most common example of length contraction" Please link to articles, and talk about statements in these articles, so we have something that is appropriate to discuss here. This is core behavior in discussing articles, and not optional, per WP:NOTFORUM.
"well credentialed philosopher" Which credentials would that be? I'm not aware that Ross holds a chair in physics, or has published in the field. Neither am I aware of his work in idealistic philosophy. If you wish to make a case that his self-published paper should count as a reliable source, provide reliable sources for such credentials.
""Philosophical Criticism" subsection (the personal opinion of the editor presenting that section!)" That is not an acceptable reading of the intentions of the editors who have produced this section, and provided it with 22 citations.
Paradoctor (talk) 23:57, 22 November 2013 (UTC)

First, I apologize yet again for my obvious lack of skill at navigating this site and my ineptitude at implementing all the many required technicalities. I am a retired philosopher/psychologist who came late in life to this wonderful world of complex technology. My primary criticism of the Criticisms of Relativity section is that relativity is based on idealism in denial of a "real world," so the philosophy of realism is rejected out of hand, as are all "criticisms of relativity," (making the section title a sham), and I have cited Einstein's own words as the "father of relativity" in conformation of his denial of a real, objective world independent of observation. (I don't know how to link to that quote directly. It can be found in DVdm's link to our 'chat' above in this section.) I also cited Kurt Godel as confirming the above. Here is a link discussing his article,

“A remark about the relationship between relativity theory and idealistic philosophy”: http://theinductivistturkey.wordpress.com/2013/04/17/godel-on-idealism-and-time-travelling/ Godel said: "Following up the consequences [of the relativity theory, particularly of the general one] [...] one obtains an unequivocal proof for the view of those philosophers who, like Parmenides, Kant, and the modern idealists, deny the objectivity of change and consider change as an illusion or an appearance due to our special mode of perception. (p. 202)" I am told that Henry Lindler's philosophy (see* below) confirming the above is not acceptable, as he is just an MD with a "hobby" of philosophy and has no proper "training" in relativity, the requirement for credentials in the field. Yet no one who criticizes relativity can acquire such credentials. (See the problem?)*Beyond Relativity and Quantum Theory to Cosmic Theory. (the latter saying that the world is in fact "real," and independent of our measurements of it, which "result from our interactions with the cosmos," i.e., that each different measurement does not create a different "world.")

Regarding Kelley Ross, his website http://www.friesian.com/ross/ has a list of his contributions to the field. But, of course, he does criticize the assumptions underlying relativity, so he is "not to be taken seriously" according to the editors here. I'll leave it for now and invite further comments. Ps: Wiki" Length Contraction section I mentioned is of course not a subsection of the Criticisms section being discussed here. Sorry I did not make that clear. I was replying to DVdm's statement about contracting objects (like Earth's diameter) vs variations in measurements of those objects. Also there is s section in Wiki on the ladder and barn paradox https://en.wikipedia.org/wiki/Ladder_paradox to which I referred. Again, I need to learn proper link notation.LCcritic (talk) 20:58, 23 November 2013 (UTC)

You are not "told that Henry Lindler's philosophy confirming the above is not acceptable, as he is just an MD with a "hobby" of philosophy and has no proper "training" in relativity". You are told about his lack of credentials, wich by the way is entirely irrelevant for Wikipedia. But it seems to be very relevant for the fact that we can't find any reliable secondary sources about him and his criticism. That lack of reliable secondary sources is the reason why we cannot include him here. As I said before, "any MD with a hobby can play the critic of anything they weren't properly trained in, but if they are ignored, they have no place here." This is just Wikipedia by design. You will have to accept that. - DVdm (talk) 21:37, 23 November 2013 (UTC)
"lack of skill at navigating this site and my ineptitude at implementing all the many required technicalities" Nobody is out to WP:BITE new editors. If you have questions, ask them. Wikipedians are generally quite willing to help out their fellow editors with information and advice. Don't forget to listen to the answers, though. You can learning about linking at WP:LINK. The central starting pointing for help is at Help:Edit. If you have questions, just ask.
This discussion does not turn on "technicalities", but on a core principle of Wikipedia. Let me spell it out as brutal as possible.
principle Whatever opinion you have, Wikipedia is not interested. Wikipedia is also not interested in discussing it.
qualifier If and when your opinion is published in a reliable source, and carries due weight, then it can and should be included.
This implies that whatever statements you want to include must be sourced to reliable sources when challenged to do so. You have been told that Ross' and Lindler's websites do not qualify because they are self-published, and the authors have not been shown to be experts in the field. Ross himself only lists one(!) peer-reviewed publication. This implies that, whatever opinion he holds is either a WP:FRINGE viewpoint, or there are better sources for the same opinion.
The Einstein quote does not, in my opinion, support your claim that Einstein denied the existence of a real world. If you wish to use it in this way, find a reliable source saying that the quote is to be interpreted in this manner, or find other reliable sources to support this position. Again, do not bother to bring up opinions from self-published or otherwise unreliable sources again.
Gödel is at least a plausible starting point. Now, before we try to find out whether this quote actually supports your claim, the first thing we need is the source of this quote. Some random blog merely claiming that Gödel said it is not good enough. Quotes are misattributed all the time. Can you provide the necessary information? For more info on citing, see WP:CITE. Take your time, there is a lot of info, and I know from experience that finding what you need to know can take quite some time. If you get stuck, you can always ask at the help desk. Qapla'! Paradoctor (talk) 23:08, 23 November 2013 (UTC)
I already sourced the Godel quote: http://theinductivistturkey.wordpress.com/2013/04/17/godel-on-idealism-and-time-travelling/ I have no idea what better reference you are asking for. His article is extant, historical and available. You said: "The Einstein quote does not, in my opinion, support your claim that Einstein denied the existence of a real world." Please re-read the full text of the quote. He did deny the statement affirming a 'real world' and he did grant that regardless of Study's defense of natural science investigating the "real world," that he, Einstein, was still "not a realist."

Your opinion as stated above (regardless of your seniority here) does not automatically negate my opinion that he said exactly what he meant, that he was not a realist. What do you think is the alternative to realism? It is idealism. I taught the difference as a university professor. What are your credentials supporting your opinion, as stated? LCcritic (talk) 01:03, 24 November 2013 (UTC)

I think that you are misunderstanding what Einstein was trying to say. He is not denying that things exist. Rather he is questioning what the word "real" means when applied to them. Are we to categorize existents as real existents versus unreal existents? What then is an unreal existent? What properties do real things have that unreal things lack (or vice versa)?
In ordinary speech, "reality" is a property that may or may not apply to ideas. We have an idea of chairs. This idea is real because chairs actually exist with the properties which we think they have. We have an idea of fairies. This idea is unreal because fairies do not exist. However, you are not using the word "real" in this sense. You are using it to mean something else. What do you mean by it? JRSpriggs (talk) 02:04, 24 November 2013 (UTC)
That you didn't indent your reply strengthen my impression that you are not exercising proper attention to detail. If you can't be bothered with simple things like that, what does that tell about your attention to Wikipedia's content rules? I didn't fix it for you this time, do it yourself.
As regards the source for the Gödel quote, you did not take into consideration what I said before, so I repeat it: A blog is not a reliable source. Also, I'm pretty sure that Gödel never blogged. So, from what reliable source does this quote originate? Note that the WP:BURDEN of proof is on you. It is not my job to hunt for possible citations for material you want to add. If you can't clear this hurdle, then you are in the wrong place, and some other forum would be better suited to your needs.
"He did deny the statement affirming a 'real world'" That is your opinion, but I don't share it. If you wish an explanation, mail me. We will not discuss this here, as it would violate WP:NOTFORUM. Again, the WP:BURDEN of proof here is on you, as you want to put this in the article.
"your seniority here" You have a misconception about this community. There is no concept of "seniority" on Wikipedia. I did not once make reference to myself as an authority for anything. If there were requests not sourced to community rules, cite them and I'll correct that.
"my opinion that he said exactly what he meant, that he was not a realist" I quote from my previous post: "Wikipedia is not interested in your opinion." Or mine, for that matter.
"What do you think is the alternative to realism? It is idealism. I taught the difference as a university professor." In that case, you better head over to philosophical realism. The article is in very poor shape, and would benefit very much from an expert adding reliable sources and expanding it.
"your credentials supporting your opinion" If you're referring to my opinion on the Einstein quote, then none are required, as stated above.
Don't forget to fix your indentation. Paradoctor (talk) 02:53, 24 November 2013 (UTC)
I hope the (:) fixed my indent above and indented this properly.(Still struggling with it.) Regarding Paradoctor's: “So, from what reliable source does this quote originate?" [Kurt Godel ref: “A remark on the relationship between relativity theory and idealistic philosophy”, Albert Einstein: Philosopher-Scientist (Library of Living Philosophers), P. Schilpp (ed.), La Salle, IL: Open Court, 1949, pp. 555–562. Reprinted in Gödel 1990, pp. 202–207.] In the article he makes the case that relativity is based on idealism, which philosophy does in fact deny a "real world" independent of observation. As I have directly quoted here, Einstein denied the statement, "The physical world is real," and in fact said, "I concede that the natural sciences concern the “real,” but I am still not a realist." That philosophy became the basis of SR's insistence that measurements determine the length of things and the distances between them, even though measurements of the same object or distance will vary with the relativistic frame from which measurements are taken.
Regarding the editorial denial, in the Philosophical Criticisms subsection, that any philosophers understand the non-Euclidean basis of relativity, I cited Kelley Ross, a credentialed philosopher of science, demonstrating a thorough understanding and intelligent criticisms of the underlying assumptions, yet his contribution is not here deemed an acceptable philosophical criticism. The lead statement of the Criticisms section still stands with no debate allowed, that no criticisms of relativity are to be taken seriously. (See again my "Catch 22" reference.)Paradoctor suggests that I take my expertise on the philosophies of realism and idealism over to the Philosophical Realism section. There, "scientific realism" is presented as the new version realism, based on the preposition that measurements determine what is real (ergo, different measurements of, say Earth's diameter mean that it varies with the frame measuring it.) I see no reason to believe that my editorial contributions there would be any more acceptable than in the section discussed here. Measurements as determining "reality" remain the bedrock philosophy for relativity. (Seriously, a 4000 mile Earth diameter is considered "equally valid" with the proper length diameter measured from at rest with the Earth frame... "no preferred frame.") Proper indentation and sourcing protocol seem to be considered more important among the editors here than any fair representation of critical perspectives on relativity. LCcritic (talk) 19:57, 27 November 2013 (UTC)
"I hope" [...] "indented this properly.(Still struggling with it.)" [...] "Proper indentation and sourcing protocol seem to be considered more important among the editors here than any fair representation of critical perspectives on relativity." You shouldn't "hope", you should know. The instructions are simple enough: indent one level more than the comment you're replying to. That has not happened. Assuming that you're trying to comply leaves the conclusion that you have serious trouble understanding the instructions. Indenting is simple. Content rules are not quite as simple. You have been repeatedly told by several experienced editors that the content rules do not allow the changes you propose, and you have been given reasons and links for that. If you're neither capable of following instructions nor willing to listen to advice from the community, you don't belong here, plain and simple.
The "sourcing protocol" you refer to is fundamental to a "fair representation of critical perspectives on relativity". If you don't understand that, you don't belong here, plain and simple.
Gödel: Closer, but still not a proper citation. Since you at last moved in the right direction, I'll make this one easy for you: WP:SAYWHEREYOUGOTIT means that the full citation includes the blog where you found it. Which isn't a reliable source.
For the sake of discussion, let's assume you actually read Gödel's paper, and the quote was in it. It still would not support your claim that Einstein denied that "The physical world is real.". It would at most allow saying that according to Gödel, relativity implies the claim made by some philosophers that change is not real. This is much less than saying that the world is not real. If you disagree with this interpretation of Gödel, that is just fine. But then you'll have to support your interpretation with reliable sources explicitly stating your point of view. In a work anyone can edit, this is not optional. Works the same for all of us.
"I cited Kelley Ross" Do not bring Ross up again here. You have been told that his site is not a reliable source. If you disagree, go to WP:RSN. Read and comply with the instructions at the top of the page before posting anything there.
Let us all remember that there is no hierarchy of authority here ("wink, wink!"), so when Paradoctor decides that I am "not willing to cooperate in a constructive manner" with the technical protocols here (that has a familiar ring)...

(not guilty... I am just severely lame at all such technicalities, as I have repeatedly pleaded), and when he essentially "bans", me form the editorial conversation here, please remember that not all critics of relativity are cranks (I have cited a few, all rejected)) "not to be taken seriously", as the section lead warns. That is all I have to say on the subject. There is no hope for critics of relativity to have a fair hearing among the editors here. LCcritic (talk) 01:25, 28 November 2013 (UTC)

## Articles are distorted by inappropriately introducing the concept of relativity.

Let me state now that I am a firm believer in Relativity. As an example of my complaint take the article on the Kennedy-Thorndike experiment. The experiment was intended to detect the presence of the Aether notwithstanding that the Fitzgerald-Lorentz contraction effect might operate. The conclusion of the experiment is that the Aether hypothesis remains viable only if a second effect, time dilation as a function of Aether velocity, is also present. This conclusion is not emphasized in the article. Instead the article refers to the relevance of the experiment to Relativity. As the relative velocity between the observer (the experimenters) and the observed body (the apparatus) is zero no relativistic effects can occur. A further example of this distortion is seen in the article the Luminiferous Aether. The reasons for a belief in the Aether are not properly (if at all) given. Too much space is given to the history of the attempt to determine the properties of the Aether rather than to the latest knowledge. The article gives the impression that the reader does not need to know the arguments for and against as modern Physics accepts Relativity and denies the Aether hypothesis. There are other articles that suffer badly from this bias towards Relativity which I will cite if required to do so.RFNo (talk) 12:19, 17 February 2014 (UTC)

## From no archives to too many archives

I felt that we needed some archives for the sections of talk above. But I was careless in setting it up, and the result was that Lowercase sigmabot III created too many archives. Sorry. JRSpriggs (talk) 12:59, 19 February 2014 (UTC)

In an edit summary, DVdm asks "Should this large number of tiny archives be consolidated by year?". Yes, I think that would be a good idea, but I worry about what to do with the archives divided by month after the consolidation. JRSpriggs (talk) 01:10, 23 February 2014 (UTC)
After the copy we can just tag them for {{db-g6}} maintenance delete. Ok if I go ahead, creating the archives, moving the content and tagging for delete? - DVdm (talk) 09:35, 23 February 2014 (UTC)
OTOH, there's so little there, that even yearly archives are too small. Perhaps we can just copy/paste everything back in here (or archive to /Archive 1) and disable automatic archiving altogether? - DVdm (talk) 10:23, 23 February 2014 (UTC)
The easiest way to do that is just to revert to the version before I put in the invocation of archiving and then re-add subsequent talk. I am doing that with this message.
It remains to remove the archives and create a new Archive 1. JRSpriggs (talk) 11:34, 23 February 2014 (UTC)
Ok, I'll have the stray archives deleted first, and then I'll create Arch1. - DVdm (talk) 11:58, 23 February 2014 (UTC)
Archived everything up to and including 2012 in /Archive 1. - DVdm (talk) 12:19, 23 February 2014 (UTC)
To DVdm: Thank you for your help in cleaning up the mess that I made. JRSpriggs (talk) 00:19, 24 February 2014 (UTC)
No problem. Isn't creating a good mess every once in a while just what makes life interesting?   - DVdm (talk) 07:59, 24 February 2014 (UTC)

## Article on time correction

Dear Editors,

I have a secondary reference in and am trying to add features of my articles in relativity: 1) http://en.cyclopaedia.net/wiki/Light-time-correction-1 for science article on time correction and momentum and energy for inverse relationship (Light time correction in science in very bottom of research gate) 2) my Pharmasug 2011 articles are peer review too and discuss relativity and uncertainty) 3) my Global SAS Forum 2012 paper also has reference to time calculations, energy correction, charge/energy of electrons plus derivations. 4) Hitchhikers guide to galaxy website is also mentioning my work time correction, http://hitchhikersgui.de/Wikipedia_talk:Articles_for_creation/Time_correction

5) Google Nepon japan website too mentions my site: http://wpedia.goo.ne.jp/enwiki/Wikipedia_talk:Articles_for_creation/Time_correction

-I can mention my discussions and example of support for inverse relationships of time and energy/momentum and velocity supported by kaufmann/Bucehrer/Neumann experiment Agravat series graph too of decrease in velocity for trend in hyper-geometric series - Time correction proofs that work for special relativity/momentum/photoelectric effect - discussion of first law of thermodynamics support in AJST article of inverse relationships of momentum and energy in New Methods of Time correction, energy, Heisenberg uncertainty principle article I discuss this in anomaly section -Time correction and right triangle relationship exists because right triangle is discussed by Einstein plus low rest mass in E=mc2)

These are some of the points I want to add please. Thank you,

Magravat (talk) 17:06, 20 February 2014 (UTC)MAgravatMagravat (talk) 17:06, 20 February 2014 (UTC)

I have added a section header. I don't see any reliable secondary sources—see wp:reliable sources—that would warrant inclusion in any article of any part of your (twice) rejected article for creation. This clearly is original research (see wp:OR), which is, alas, not allowed here. - DVdm (talk) 17:54, 20 February 2014 (UTC)

Dear DVdm,

Thank you. I have added some articles citation in a secondary resource Science20.com as 'Upstart Bio-statistician' column where I include many articles on Principal Quantum Number, energy and time correction, plus Bose Einstein Condensate and Energy Correction in the wikipedia Articles for creation site. Will this help the article making process for wikipedia? I also referenced one in the wiki.

Thank you,

User:Magravat Magravat — Preceding unsigned comment added by Magravat (talkcontribs) 23:45, 17 April 2014 (UTC)

User:Magravat Thank you Kvng, Annie, Starry Grandma, and , Rankersbo, too.

Magravat — Preceding undated comment added 23:41, 19 April 2014 (UTC)

## Popular pages tool update

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## Expert attention

This is a notice about Category:Relativity articles needing expert attention, which might be of interest to your WikiProject. It will take a while before the category is populated. Iceblock (talk) 18:24, 11 December 2014 (UTC)

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## Website

I would like to add Hyper Physics to the websites section as I think is a useful undergrad level introduction to relativity. Please feel free to comment if you have opinions. PennyDarling (talk) 11:22, 8 August 2015 (UTC)

Please don't do that. They don't understand the bug rivet paradox. More silliness from the same site: "Accelerations are outside the realm of special relativity and require general relativity." Bad Source. To be avoided at all cost, at least for relativity. I have written them a few emails about this. Never got a reply. - DVdm (talk) 12:14, 8 August 2015 (UTC)
Can you supply a reference that you think is valid so that this can be reviewed? PennyDarling (talk) 10:08, 9 August 2015 (UTC)
I think Google might be your friend :-) - DVdm (talk) 12:04, 9 August 2015 (UTC)
I have assumed good faith in your first reversal, but since you cannot supply citable references for removing this link, I have reversed this edit for the time being. Please cite references behind you decision as per Wikipedia policies and guidelines of NPOV, WP:OR, WP:V, WP:RS. This resouces has been developed by a professional with expertise in the subject and has been reviewed by, amongst others the IoP and SciLinks. — Preceding unsigned comment added by PennyDarling (talkcontribs) 12:36, 9 August 2015 (UTC)
Please sign all your talk page messages with four tildes (~~~~). Thanks.
I notice you just reinserted that link. I have reverted it again. The site makes two glaring errors. Let's discuss this first. See wp:BRD. - DVdm (talk) 12:42, 9 August 2015 (UTC)
I really don't want this to descend in to an edit war, so I am requesting assistance. Meanwhile I would ask you to please supply citable reference for your decision and claims as per NPOV, WP:OR, WP:V, WP:RS. I have reverted, in the meantime (until you can supply citations), to the original state as the reference has credible citation and professional review. PennyDarling (talk) 13:22, 9 August 2015 (UTC)
If you don't want this to descend in to an edit war, then you don't revert again, and we keep this "article" in its original shape until the matter is resolved by consensus. See—again—wp:BRD. Per wp:NOCONSENSUS (" a lack of consensus commonly results in retaining the version of the article as it was prior to the proposal or bold edit."), I have restored the original content, awaiting consensus here. Do have a look at wp:3RR.
By the way, for few links regarding the bug rivet paradox, see, for instance, [1], [2], [3], [4], etc...
Now, do have a serious look at, for instance, http://hyperphysics.phy-astr.gsu.edu/hbase/Relativ/bugrivet.html#c1, where they claim that "the paradox is not resolved." That means that they think that there is a serious problem with special relativity. Here in http://hyperphysics.phy-astr.gsu.edu/hbase/Relativ/twin.html#c1 they say that "accelerations are outside the realm of special relativity and require general relativity." So, what about you, do you think that accelerations are outside the realm of special relativity and require general relativity? Do you think that the bug rivet paradox cannot be resolved? - DVdm (talk) 20:01, 9 August 2015 (UTC)
Having followed your links, these appear to be personal web pages and Forum discussion groups - I'm afraid that these are not acceptable as credible academic examples. Furthermore, this appears to me to be a NPOV issue in that you take exception to a small part of an otherwise creditable resource; I would like to reiterate that this talk section is not for the discussion of personal beliefs or theories, but to provide resource to academic, mainstream materials. PennyDarling (talk) 08:39, 10 August 2015 (UTC)

Please wait for the conclusion of the discussion before making edits - I will read your comments and respond in de course. PennyDarling (talk) 20:56, 9 August 2015 (UTC)

Repeat: Per wp:NOCONSENSUS: (" a lack of consensus commonly results in retaining the version of the article as it was prior to the proposal or bold edit."). - DVdm (talk) 21:01, 9 August 2015 (UTC)

Please wait for the conclusion of the discussion before making edit. We have not fully discussed this yet, so we can not yet conclude that this is wp:NOCONSENSUS PennyDarling (talk) 08:17, 10 August 2015 (UTC)

I wold like to add further web references to this project page over the next few days. Please feel free to discuss here any of these resources here. PennyDarling (talk) 08:39, 10 August 2015 (UTC)

I have reported you for edit warring at Wikipedia:Administrators' noticeboard/Edit warring#User:PennyDarling reported by User:DVdm (Result: )
Meanwhile, regarding acceleration and special relativity, see for instance
and more at
- DVdm (talk) 08:53, 10 August 2015 (UTC)
By the way, that Wolfram site that you just added is even worse. Just have one look at the glaring error on http://scienceworld.wolfram.com/physics/SpecialRelativity.html where they have the time dilation equation completely wrong. That should be t'=γt0. Note that I have emailed Eric Weisstein to correct this too. I got a deafening silence from there as well, just like from Hyperphysics. Perhaps we can keep these sites in the page, provided we change the header from Websites to Bad websites, or to Websites to be avoided. , , any thoughts? - DVdm (talk) 09:10, 10 August 2015 (UTC)
• do you think that accelerations are outside the realm of special relativity and require general relativity?
• do you think that the bug rivet paradox cannot be resolved?
- DVdm (talk) 09:15, 10 August 2015 (UTC)
Firstly, this should not be not about personal opinion, this is about quality of resource. Secondly, simply because you disagree with it does not make it wrong, it is simply a different opinion - which is quite acceptable and should be reported upon. I am not prepared to get in to a discussion on beliefs; I trained in Theoretical Physics and I still don't entirely trust theorems, let alone theories. PennyDarling (talk) 13:16, 10 August 2015 (UTC)
So I take it that you think that accelerations are outside the realm of special relativity, and that the bug rivet paradox cannot be resolved. It also shows that you have no objection to promoting non-peer reviewed websites that clearly contain elementary conceptual errors, the authors of which ignoring repeated friendly suggestions to correct these errors. This suggests that you hold a fringe view on the subject matter, and that— see wp:FRINGE—your best bet might be to avoid special relativity subjects on the Wikipedia. Note that Wikipedia works by wp:CONSENSUS, and that in this case the consensus is against you. - DVdm (talk) 13:44, 10 August 2015 (UTC)
I agree with DVdm. The hyperphysics.phy-astr.gsu.edu does seem to have some serious issues and the Wolfram site does have a, rather surprising, mistake. SR, rather like, centrifugal force, is an area of physics that seem to attract many misconceptions, particularly online. We need to make sure that all links contain solid current physics. Martin Hogbin (talk) 11:18, 10 August 2015 (UTC)

Note - User PennyDarling was blocked for 24 hours ([5]). - DVdm (talk) 14:16, 10 August 2015 (UTC)

To PennyDarling: Regarding the bug rivet paradox, there appear to be errors in the calculation, but even if one corrects those, the two events bug-squashed-by-end-of-rivet and wall-struck-by-head-of-rivet are separated by a space-like interval. So one cannot say that one event occurs before the other in all reference frames. What will happen is that the bug will be squashed (indeed vaporized or worse) and the rivet will break (or worse). The bug's argument that he will survive is based on the false assumption that the rivet and the wall are perfectly rigid. But perfect rigidity cannot exist in special relativity. Thus there is no real paradox. Because the website does not explain how the paradox is resolved, but claims falsely that it cannot be resolved, the website is actually anti-relativity and should not be used as a reference. JRSpriggs (talk) 06:47, 11 August 2015 (UTC)
Hi JRSpriggs, thanks for the input, I really appreciate it. However, I'm afraid that's not the point: solutions to the bug-rivet paradox are trivial. The issue is acceptance that Wikipedia is an encyclopedia and provides a description of a subject, regardless of our personal beliefs. Many of the links I've seen here come from blogs and forums, which is not what wikipedia is really about (WP:NEWSBLOG, WP:NOTRELIABLE). I really wanted to contribute and improve the articles here because when I was at university (both of them), wikipedia was treated as a joke: it was often said that is was so badly written and referenced that it was often referred to as shittipedia. This topic is a theory - it isn't fact, it isn't a truth, it's merely a description which open to interpretation. I think that including and informing on opposing (qualified and expert) interpretations is healthy. I really think that this topic would benefit from a more neutral edit using reliable, pertinent and diverse citations; what it is not is a forum for discussion on the subject. Again, many thanks for taking time to reply - appreciate it. PennyDarling (talk) 15:05, 11 August 2015 (UTC)
Penny, all science articles in WP should be written from the viewpoint of mainstream science. The theory of special relativity is now well over 100 years old and it is well understood. It is not a 'description which open to interpretation' but what would generally be called 'fact'. Of course, physicist well know that SR is not exact and that it may well be superseded by a better theory one day, however, it is, within its realm of applicability, the best theory that we have today and it is part of mainstream science. There are no 'opposing (qualified and expert) interpretations' of SR only some opposing (unqualified and wrong) interpretations.
I understand your concern about bad sources and the best way to approach the problem is to look for the highest quality sources for anything you think needs one. Good textbooks by established quality publishers and peer-reviewed journals are the best sources for science. The links you want to add are to web sites with errors and thus are not appropriate for WP but only for SP. Martin Hogbin (talk) 16:23, 11 August 2015 (UTC)
Hi Martin, thanks for the reply. This is a little off topic now, but you say "There are no 'opposing (qualified and expert) interpretations' of SR only some opposing (unqualified and wrong) interpretations." I'm not trying to promote any ideas here myself, but in the history of scientific theory, none have have even been proven "right" so I really don't how you can claim that some are definitely "wrong". I think that the problem with the amateur scientist is that they lack rigour (e.g. quoting forums) and want to singly promote their own beliefs and deny others. This project is slipping down the quality scale for a reason. PennyDarling (talk) 07:30, 12 August 2015 (UTC)
To be more clear, the effect of the rivet head striking the wall cannot propagate instantaneously, but only at light-speed or slower. Thus it cannot prevent the end of the rivet from squashing the bug.
We editors must use our own expert judgement to evaluate potential references. There is no automatic process for vetting references. JRSpriggs (talk) 06:25, 13 August 2015 (UTC)
Indeed, "at light-speed or slower", which would effectively be at the material sound speed  . - DVdm (talk) 10:09, 13 August 2015 (UTC)
The bug-rivet is a rather poor paradox anyway because what happens in all frames is is that the bug, along with the rivet and anything else nearby, is rapidly converted to a ball of plasma. Martin Hogbin (talk) 14:57, 20 August 2015 (UTC)

## redirects

There are several red-link redirects I cannot create ... could someone please do these?

The article congruence (general relativity) gives a nice discussion of congruences, expansion, and vorticity (and shear) in general relativity. Thus, hypersurface orthogonal and vorticity tensor can be redirects to congruence (general relativity). Then congruence of curves can be a redirect to congruence (manifolds).

Some more mathy redlinks could use help: convergent expansion -> radius of convergence and operator product algebra -> operator product expansion Thanks!! 67.198.37.16 (talk) 18:38, 21 February 2016 (UTC)

Thanks! 67.198.37.16 (talk) 06:07, 23 February 2016 (UTC)

## Help over at AfC

Could we get some eyes on a draft over at AfC, Draft:Non-Inertial Reference Frames in Relativity? Any comments, direction would be greatly appreciated. Onel5969 TT me 12:56, 13 May 2016 (UTC)

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## A possible error in the article about Gravitational Lensing Formalism

In the article Here, in the end of the section "Weak lensing observables>Shear and reduced shear" (section=8), it says that ${\displaystyle \langle \epsilon \rangle =\langle \gamma \rangle }$ . However, when going through the review about GL written by Bartelmann & Schneider (the first reference in that article), it says in page 341 (p. 51 in the PDF) that ${\displaystyle \langle \epsilon \rangle =\langle g\rangle }$ . Meaning, it's equal to the reduced shear parameter, and not to the shear parameter.

Also, it is implicitely assumed in the written definition of ${\displaystyle \epsilon }$  that ${\displaystyle |g|<1}$  - see equation (4.12) in that review.

Erez Zinman (talk) 14:19, 6 February 2018 (UTC)

## Criticism of the Lorentz Transformation

The Wikipedia section Criticism of the theory of relativity is incomplete. As is the case for the sections Theory of relativity and Lorentz transformation, there is no instance which questions the viability of the Lorentz transformation (LT) in itself. It is incomplete and therefore faulty. It ignores a contradiction between two of its most famous predictions, namely proportional time dilation (TD) and remote non-simultaneity (RNS). This conclusion is justified upon consideration of the following four statements, which should be answered with either YES or NO with regard to their correctness:

1) Multiplying a finite number with zero always results in a value of zero;

2) Accordingly, it is impossible for two time differences ΔT and ΔT' to always be proportional to one another (ΔT'=XΔT), where X is finite, and yet have ΔT'≠0 (non-simultaneous observation) while ΔT=0 (simultaneous observation);

3) A proportionality relationship (ΔT'=XΔT) between time differences measured for the same events by two different observers in relative motion to one another is the consequence of the phenomenon of time dilation (TD) in Einstein's Special Theory of Relativity (STR), while the other (ΔT=0 and ΔT'≠0), referred to as remote non-simultaneity (RNS), is also predicted by the same theory;

4) The fact that both TD and RNS are predicted by the LT to occur in experiment and yet are shown above to be mutually exclusive is incontrovertible proof that this relationship between space and time is not valid.

Since the only correct position on all four of the above questions is YES, it follows that a key aspect of Einstein's STR is false. In particular, it shows that the LT needs to be replaced in the theory by a different space-time transformation that a) satisfies both of Einstein's postulates of relativity, namely Galileo's Relativity Principle and the constancy of the speed of light in free space, but b) does not suffer from the above conflict inherent in the LT.

Robert J. Buenker --RobertJBuenker (talk) 15:33, 25 April 2019 (UTC)

2) Beginner's mistake. Check the transformation in standard form: Δt'= γ (Δt - v/c^2 Δx) and Δx'= γ (Δx - v Δt), where, for readability, I have also adjusted your notation.
Assuming that your X is γ, the case Δt'=γ Δt is only valid for events that satisfy Δx=0, i.o.w. that have the same x-coordinates, and that thus are colocal in the unprimed frame. In that special case, when you assume that also Δt=0 (simultaneous and colocal in the (x,t)-frame), you really have only one single event, and so obviously you also have Δt'=0, and of course Δx'=0. Both transformation equations trivially reduce to 0=0, or if you like, to 0=X 0, for any X you fancy.
Assuming that your X is 1/γ, a similar argument with the inverse transformation is left as an exercise. - DVdm (talk) 16:15, 25 April 2019 (UTC)
The claim that the Δt'=γΔt case is only valid for Δx=0 is wrong. The standard derivation of time dilation considers a special case in which Δx=vΔt. This point is made in Jackson's book (Classical Electrodynamics, Wiley, New York, 1962) on p. 359 (he uses z instead of x). This substitution in your equation for Δt' directly to Δt/γ, where X=1/γ in my notation. The same result is obtained from the Lorentz invariance equation when the Δx=vΔt substitution is made, as pointed out in other textbooks. Time dilation is a standard prediction of the LT for the time difference of the same pair of events such as lightning strikes occurring at two different positions in the forest when observed by two different bservers in relative motion. --RobertJBuenker (talk) 12:33, 26 April 2019 (UTC)
You make the classic beginner's mistake: this is physics, not just mathematics, and you don't take into account (—because i.m.o. you clearly don't understand(*)—) the physical meaning of the variables x, t, x', t' in the transformation equations.
(*) The equation Δt=0 does not mean "simultaneous observation" as you seem to think. The equation Δt=0 means that you are talking about "two events that have the same time-coordinate in the (x,t)-frame", so it means that the events are measured (or calculated) to be simultaneous. Your phrase "simultaneous observation" has nothing to do with that, and may very well lie at the heart of your confusion. It does not matter whether you observe the events simultaneously. The events must happen simultaneously. How or when you observe them is entirely irrelevant.
Also, regarding your declaration "The claim that the Δt'=γ Δt case is only valid for Δx=0 is wrong": the equation Δt'=γ Δt says that the time interval Δt' as measured in the (x',t')-frame between two ticks on a clock that is at rest in the (x,t)-frame, is longer by a factor γ than the time Δt between these ticks of the clock in its own rest frame. "At rest in its own (x,t)-frame" is exactly what is modeled by Δx=0 for the tick events: no spatial separation between the tick events, same x-coordinate, thus Δx=0.
Look at the transformation equations Δt' = γ (Δt - v/c^2 Δx) and Δx' = γ (Δx - v Δt) and their inverse Δt = γ (Δt' + v/c^2 Δx') and Δx = γ (Δx' + v Δt'). The instant you talk about two events of which the coordinates satisfy Δt'=X Δt, you immediately restrict the event coordinates to also satisfy Δx=0 or Δx'=0. If you then also write Δt=0 or Δt'=0, then you can algebraicly verify that everything immediately collapses to Δx=Δx'=Δt=Δt'=0. The linearity of the transformation guarantees that when any two deltas are zero, then all four deltas are zero, a trivial high-school property of linear transformations. Physically this means: when two events happen simultaneously and at the same place as measured in one inertial frame, then the events happen simultaneously and at the same place as measured in all inertial frames. In fact you are talking about one single event, not about two distinct events.
Note: also, please be aware that Wikipedia is not the place to publish or even discuss our own original research—see for instance wp:NOR and wp:TPG. All articles should reflect the current common views, as opposed to deviating less common (fringe) views—see for instance wp:FRINGE and wp:UNDUE. And of course, Wikipedia is not the place where we are supposed to help each other getting rid of misconceptions—see wp:NOTFORUM. Perhaps you can visit a proper off-wiki discussion forum about this. It's really simply though, provided one understands the actual meaning of the variables in the equations that model the physics, and of course, basic linear algebra. Good luck! - DVdm (talk) 13:31, 26 April 2019 (UTC)
To RobertJBuenker: You need to understand that it is meaningless to talk about a time (or difference of two times) without reference to the associated place or places. Events occur at a time and place, not just a time. JRSpriggs (talk) 01:13, 27 April 2019 (UTC)

Rather than try to undo the longstanding derivation of proportional time dilation, which goes back at least to Einstein's 1905 landmark paper on the Special Theory of Relativity, it would be far more productive to move forward to accept the conclusion of my April 19 critique given in its fourth statement. The currently accepted version of relativity theory needs to be fundamentally revised. It is no longer acceptable to base this theory on the Lorentz transformation (LT). This fact needs to be presented forcefully to your colleagues who have also accepted the responsibility of guaranteeing the essential truthfulness of what is claimed regarding this subject by Wikipedia. This group should include at a minimum the following two recognized authorities in this field:

Prof. Freeman Dyson Institute for Advanced Study School of Natural Sciences Einstein Drive Princeton, NJ 08540 Phone: (609) 734-8055 Cell: (609) 731-5657 Fax: (609) 951-4489 dyson@ias.edu

Clifford M. Will Distinguished Professor of Physics Department of Physics Institute for Fundamental Theory Institute for High Energy Physics and Astrophysics University of Florida P.O. Box 118440 Gainesville FL 32611-8440 352-392-5707 352-392-5339 (fax) cmw@phys.ufl.edu

The replacement for the LT which is mentioned at the end of my critique has already been published recently in J. App. Fundamental Sci. 4 (1), 6-18 (2018), as well as in my book: Relativity Contradictions Unveiled: Kinematics, Gravity and Light Refraction, Apeiron, Montreal, 2014, pp. 55-56. This transformation does indeed satisfy both of Einstein's postulates of relativity, but also eliminates any possible contradiction involving time dilation.

--RobertJBuenker (talk) 15:51, 27 April 2019 (UTC)

Merely having a look at Jackson 359 that you mentioned earlier (and adjusting the notation):
"We assume that the meson is created at the origin of K' at time t'=t=0. As seen from the system K the position of the meson is given by x=v t. If it lives a time T0 in K', then at its instance of decay, we find t' = T0 = γ (t - v/c^2 x) = 1/γ t (eq 11.23). The time t is the meson's lifetime T as observed in the system K. Consequenlty T = γ T0 (eq 11:24). When viewed from K the moving meson lives longer than a meson at rest in K'. The 'clock' in motion is observed to run more slowly than an identical one at rest.''
So there you have it: "at rest in K' " just means Δx'=0. The x=v t in Jackson is equivalent with x'=0, which is also reflected in the standard Lorentz transformation. Bottom line: the ticks of a clock at rest in a system happen at the same place in that system. Note that in our example we have swapped K and K'. So indeed "the claim that the Δt'=γ Δt case is only valid for Δx=0" is correct, and fully consistent with Jackson's page 359. Regading your statement "It is no longer acceptable to base this theory on the Lorentz transformation (LT)". Just look at your Jackson quote: he actually uses the transformation to arrive at eq 11.23.
So you have it wrong and I'm afraid that you are profoundly confused and that you have no idea what you are talking about. Unless some well-establisched wp:secondary sources mention your original research, there will be no place for it in Wikipedia—by design, see wp:FRINGE, wp:NOR and wp:UNDUE. But note that Wikipedia is really not the place to go with your problems—see wp:NOTFORUM - DVdm (talk) 16:32, 27 April 2019 (UTC)
To RobertJBuenker: Our article, test theories of special relativity, summarizes the empirical evidence in favor of the Lorentz transformation. It is very strong. JRSpriggs (talk) 01:06, 29 April 2019 (UTC)

In order to illustrate the main points of the April 19 critique of the Lorentz transformation (LT), it is helpful to consider one of Einstein's most famous defenses of remote non-simultaneity. One has two light flashes arriving at the same point on a moving train. The time difference between these two events is measured with a clock which is located on the train itself and it is designated to have a value of Δt'. The corresponding time difference measured on a clock located on the stationary platform as it is passed by the train, which is moving with speed v in the x direction, is designated to have a value of Δt. In order to apply the LT in this case, attention is focused on the train's clock. During the course of the measurements, it remains in the same position, i.e. Δx'=0 for an observer on the train. The same clock is found to be moving from the standpoint of the platform observer, however, whereby the distance traveled by it is easily computed to be Δx=vΔt from his vantage point. Under the circumstances, the relevant equation from the LT is:

       Δt'=γ(Δt-vc-2Δx).   (1)


Substitution of the Δx=vΔt relationship therefore gives

     Δt' =γΔt(1-v2c-2) = γ-1Δt,  (2)


which is the equation for proportional time dilation. Next consider the special case in which the two light flashes arrive simultaneously from the standpoint of the observer on the train, i.e. Δt'=0. There are two ways to proceed. First, from eq. (1), it is clear that Δt≠0 since neither v nor Δx is equal to zero (remote non-simultaneity). On the other hand, eq. (2) indicates with equal clarity that Δt=0 (remote simultaneity). This is an example of the general contradiction mentioned in the third statement of the April 19 critique, which in turn leads unequivocally to the conclusion in the fourth statement, namely that the existing theory based on the LT is irrevocably flawed and in obvious need of fundamental revision. In light of the comments as yet received, a few remarks on the general role of Wikipedia in scientific discourse are in order. It is a journal without an editor. There is no one to whom criticism of a particular entry can be addressed. Instead, it relies on the integrity of self-appointed colleagues who are chosen on a "first-come-first-serve" basis. Thus far in the discussion, the only replies are easily rebutted and merely show the inherent reluctance on the part of each of their authors to give serious consideration to criticism that runs contrary to their views. There is no comment which says "Gee, I am really surprised by this development. I never thought of the obvious contradiction between remote non-simultaneity and proportional time dilation for the same pair of events when viewed by two different observers." Why not? Recognition of the validity of the April 19 critique by Wikipedia is only a first step. All the existing entries on Einstein's relativity theory need to be carefully examined and incorrect material needs to be taken down from the Wikipedia website in the very near future. Ultimately, the results of this discussion need to be accepted by mainstream journals. Speaking from experience, this goal requires that pressure be placed upon the corresponding editors of these journals to send out critical manuscripts for peer review. When that eventuality comes to pass, all that will be left to do is to ensure that influential periodicals such as the New York Times publish the headline: "Einstein's Theory of Relativity Overturned by Elementary Algebra."

--RobertJBuenker (talk) 21:31, 1 May 2019 (UTC)

In the special case you are considering, the light flashes arrive simultaneously at the same point (the clock) on the train. So Δt'=0=Δx'. Thus it is also the case that Δt=0=Δx. So your assumption "nor Δx is equal to zero" is false. JRSpriggs (talk) 00:53, 2 May 2019 (UTC)
Quite. Exactly as I said before in my first reply. Setting up a situation to verify that for a single event, the coordinate differences' transformation equations all trivially reduce to 0=0. "Einstein's Theory of Relativity Overturned by Elementary Algebra", I have seen it happen dozens—if not hundreds—of times on Usenet. Always exacly the same beginner's mistake. Depending on the maker's background, sometimes a rather embarrassing one actually.
I'm afraid there's not much hope for you to ged rid of your confusion. Looking at the effort that you have put in this up to now, there might be a psychological barrier to be overcome as well, and I don't think that we can help you with that here. I recommend for instance sci.physics.relativity on Usenet. That is, if you can stand the heat. And be prepared to filter out the inherent 95% noise. - DVdm (talk) 07:14, 2 May 2019 (UTC)

It is true that the example of two light flashes meeting at the same point on the train does not lead to any contradiction, but the situation is different when the two events are separated by some distance along the direction of the train's motion.

Consider the case of two lightning strikes arriving at the front and back of the train, respectively. The platform observer finds that the distance between the two positions has a value of Δx≠0. If the two strikes arrive simultaneously for him (Δt=0), it follows from eq. (1) of the Lorentz transformation (LT)

Δt'=γ(Δt-vc-2Δx).   (1)


that they do not arrive at the same time based on the clock which is at rest on the train, i.e. Δt'≠0. This is an example of non-simultaneity.

One can use the LT in a different way for the same example, however, by focusing attention on the motion of the train's clock. By definition, it remains at the same position in the rest frame of the train throughout the measurement process, so that Δx'=0 in this application. The platform observer, by contrast, sees the same clock move with speed v along the x axis, causing its position to vary as Δx=vΔt for him. Substitution of the latter relationship in eq. (1) therefore leads to the following result in eq. (2):

Δt' =γΔt(1-v2c-2) = γ-1Δt, (2)

Accordingly, one finds that Δt'=0 whenever Δt=0. as in the present case. In other words, use of the LT in this manner leads one to the inescapable conclusion that the two lightning strikes must arrive simultaneously at their respective positions on the train. Since the latter result stands in direct contradiction to the above finding of non-simultaneity, this shows that the LT, from which both predictions derive, is unviable.

The crux of the April 19 critique (Clock Puzzle) is the incompatibility of remote non-simultaneity and proportional time dilation. Why has it taken so long for this fundamental inconsistency to come to light? While it is impossible to give a satisfactorily comprehensive answer to this question, there is an observation that goes a long way to clarifying this matter. When Einstein made the prediction of time dilation in his 1905 paper (see pp. 903-904), which is clearly based on eq. (1) of the LT, he made absolutely no mention of any relationship to the possibility of non-simultaneity that clearly follows from it. In turn, accounts of the latter consequence of the LT, such as the masterfully detailed presentation in Wikipedia itself, inevitably fail to mention time dilation either. The two predictions are always considered totally separately from one another. As the present critique makes quite clear, as soon as they are considered together it is obvious that there is an unavoidable contradiction between them which cannot be removed without eliminating the source of the problem, namely the space-time-mixing characteristic of eq. (1) of the LT. In other words, if you don't look for the problem, you won't find it, even though it is undeniably there.

Now that it has been unveiled, however, the burning question is: What is Wikipedia going to do about it?

--RobertJBuenker (talk) 16:25, 9 May 2019 (UTC)

you have effectively shown that there is indeed a (trivial) contradiction in your misconceptions of Einstein's theory of relativity. Regarding your suggestion, I don't think that the New York Times will ever publish a headline along the lines of "Buenker's Misconceptions of Einstein's Theory of Relativity Overturned by Elementary Algebra." The world is not interested in that anymore.
And of course, by design, Wikipedia is going to do nothing about it—see Wikipedia:Five pillars and Wikipedia:What Wikipedia is not. Trust me, you are severely wasting your time here. Usenet is a better place to do that. - DVdm (talk) 21:37, 9 May 2019 (UTC)
To RobertJBuenker: To measure the time of the two lightning strikes on the train, you need two different clocks on the train — one at the rear where that bolt strikes and another one at the front where the other bolt strikes. If these clocks are synchronized in the train-frame, then they will not be synchronized in the platform-frame. So your assumption that "the train's clock ... remains at the same position in the rest frame of the train throughout the measurement process" is an error. You have conflated the two train clocks into one. JRSpriggs (talk) 04:46, 10 May 2019 (UTC)

Dear Forum members,

In the beginning of Einstein's landmark 1905 paper, he gives an example to demonstrate the consequences of his light-speed postulate. Accordingly, the speed of light in free space is supposed to have the value of c regardless of the state of motion of either the observer or the source from which the light has been emitted. In his example, there is a bar of length rAB which moves at speed v along the x axis relative to the observer. At time tA, light is emitted in the forward direction from the front of the bar. At some later time tB, the light reaches the end of the bar. Einstein applies his postulate to conclude that the light reaches this point at time Δt≡ tB- tA after moving a distance of cΔt relative to the observer. During the same period, the front of the bar has traveled a distance of v Δt. By subtraction, one therefore concludes that the light travels a distance of X=(c-v)Δt relative to its source at the front of the bar in the same period of time.

This is an odd result indeed. It means that if the speed of the bar relative to the observer is close to c, then the corresponding speed of light relative to its source can be arbitrarily close to zero, the speed of a bicycle, for example. Moreover, in the reverse motion where the light moves in the opposite direction as the bar, the speed of light relative to its source can be anything just short of 2c, i.e. twice the speed of light foreseen in Einstein's postulate. Both results clash with the prediction of Maxwell's electromagnetic theory which holds that the speed of light has a value of c in any and all rest frames. Moreover, the same result of c is obtained from the velocity addition theorem Einstein also derived in his 1905paper. In that case the relative speed of the light to its source is computed as Y=(c-v)(1-v/c)-1 = c, in complete agreement with Maxwell's long-accepted theory.

The question that the above results clearly raises is how long the physics community will continue to swear by Einstein's second postulate? It needs to be replaced by a different version which assumes that the speed of light relative to its source is always equal to c independent of the state of motion of the observer. Once this step is taken, however, one has to agree at the same time that in Einstein's example the actual speed of the light relative to the observer is c+v, i.e. the sum of the speed v of the bar relative to the observer plus that of the light relative to its source while moving in the same direction as the bar. It will of course be recognized that taking this step forces one to conclude that the applicable velocity addition theorem in this example is nothing other than that of the classical (Galilean) transformation, not the version derived by Einstein.

Of course, the classical transformation does not work in all cases. The primary example is the Fizeau/Fresnel light-drag experiment. Its results upon extrapolation to light in free space lead to the simple relationship c(v)=c. The general formula for this effect was derived successfully from Einstein's velocity transformation by von Laue in 1907. Examination of the derivation of the Lorentz transformation and its precursor published by Voigt in 1879, however, reveals that Einstein's second postulate is not required for this purpose. Instead, all that is needed is the assumption that the speed of light relative to its source always has a value of c, but not that it is dependent on the state of motion of the observer.

The above discussion makes clear that it is easy to distinguish between situations for which the Galilean transformation is applicable and others where it is necessary to go over to Einstein's velocity transformation. The former must be used when there are two observers in different rest frames who are carrying out measurements of the velocity of a single object, including that of a light wave or pulse. The claim that the classical transformation is just the low-energy version of a true "relativistic" transformation does not hold water anymore.

The latter transformation that Einstein derived is intended instead for a special class of problems in which a single observer measures the velocity of an object under two different sets of conditions. This occurs, for example, when a light wave moves through a medium which is itself either at rest in the laboratory's rest frame or is moving with speed v relative to it. Another example is that of an electron as it changes its degree of acceleration in an electromagnetic field. A third one occurs in Thomas precession, in which case the path of an electron is altered from one moment to the next by virtue of its orbital motion about a nucleus. The same cannot be said for the light wave in Einstein's original example, however, since both the original observer and his counterpart at rest on the moving bar containing the light source measure the speed of the light wave at the same time under exactly the same conditions.

In conclusion, Einstein's second postulate is in clear disagreement with the results actually expected for his example of a moving light source. For more than a century now, it has been assumed by mainstream physicists that the second postulate somehow proves that the classical Galilean velocity transformation is not applicable for the case of a light wave emitted from a moving source. This misconception has to change. Therefore, it is hoped that the present detailed critique will prove to be an inflection point that soon leads to the rejection of Einstein's second postulate as a viable component of relativity theory. RobertJBuenker (talk) 18:35, 29 September 2019 (UTC)

You resumed wasting your time here. - DVdm (talk) 18:53, 29 September 2019 (UTC)
To RobertJBuenker: The errors which you attribute to the theory of relativity (and also to classical theory) are actually the result of your own sloppy thinking. You need to be more careful in making distinctions.
For example, you say "Both results clash with the prediction of Maxwell's electromagnetic theory which holds that the speed of light has a value of c in any and all rest frames.". No, they do not clash with it because in the two examples you gave the bar (and the source of the light) was moving. Thus the reference frames in question are not rest frames of the bar. JRSpriggs (talk) 09:27, 30 September 2019 (UTC)

## Request for information on WP1.0 web tool

Hello and greetings from the maintainers of the WP 1.0 Bot! As you may or may not know, we are currently involved in an overhaul of the bot, in order to make it more modern and maintainable. As part of this process, we will be rewriting the web tool that is part of the project. You might have noticed this tool if you click through the links on the project assessment summary tables.

We'd like to collect information on how the current tool is used by....you! How do you yourself and the other maintainers of your project use the web tool? Which of its features do you need? How frequently do you use these features? And what features is the tool missing that would be useful to you? We have collected all of these questions at this Google form where you can leave your response. Walkerma (talk) 04:24, 27 October 2019 (UTC)

## c

I recently made an addition to the talk page of the article Mass-energy equivalence, in which I suggested that c is not actually the speed of light. The speed of light varies depending on the medium, right? But c is the constant. It is, of course, the speed of light in a vacuum, but it's also the speed of other massless particles. So, my question is this (based on the assumption that I'm correct in any way): should the wording in the article reflect this?

I apologise for wasting anyone's time if I'm entirely wrong about this! I am not a professional in this field, and I wouldn't even call myself so much as an amateur either! --82.21.97.70 (talk) 22:48, 6 March 2020 (UTC)

## Community support invited

It appears that a highly used article, frequently relied on in the Physics Stack Exchange site, is truncated substantially, so as to avoid a perceived infraction of excess pedagogy, the way I understand it. Community support would be welcome in tweaking the deleted background sections to read less "pedagogical" (a pejorative term in the mind of some), but still useful to the dozens of physics students I know from personal experience are using it. Cuzkatzimhut (talk) 15:11, 6 May 2020 (UTC)