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A fact from 2011 OPERA faster-than-light neutrino anomaly appeared on Misplaced Pages's Main Page in the Did you know column on 19 October 2011 (check views). The text of the entry was as follows: Did you know... that physicists running the OPERA experiment detected neutrino particles apparently moving faster than light? A record of the entry may be seen at Misplaced Pages:Recent additions/2011/October.

Some theory

Someone added this info to the OPERA experiment article, but it lacks some sources.--90.184.154.70 (talk) 19:32, 9 October 2011 (UTC)

Article title

I'm not sure this is the best possible title for this article. I think it should either be sufficiently descriptive (e.g. OPERA superluminal neutrino anomaly or OPERA neutrino speed anomaly or OPERA neutrino time-of-flight anomaly) or as simple as possible (OPERA anomaly). (Personally, I'd prefer the former.) The OPERA experiment being about neutrinos, I don't think the current title is any more informative than just “OPERA anomaly”, and needlessly longer. What do you think? ― A. di M.​_plé​ 17:49, 11 October 2011 (UTC)

It sounds reasonable to me to move to OPERA anomaly. After the move it would probably useful to then redirect the current name to that page. Polyamorph (talk) 17:52, 11 October 2011 (UTC)

From a search result point of view, it is better to have the words "faster than light" somewhere in the title. That is what really interests people in the article, I presume. Ajoykt (talk) 03:57, 12 October 2011 (UTC)

We can have redirects that contains that string, if you like. Polyamorph (talk) 07:44, 12 October 2011 (UTC)

Yes. OPERA anomaly as the title with redirects for "faster than light" and from the current title sounds good. Ajoykt (talk) 15:41, 12 October 2011 (UTC)

The Van Elburg objection

Ronald Van Elburg is an AI researcher, not a physicist. His paper will never be peer-reviewed because he has not submitted it for peer review. I think the reference to his work is not credible. It is hard to believe 160 physicists working for several years, and the entire global community scrutinizing the results for a month, would have missed anything basic.

The core of the objection is that because the GPS satellite is moving with velocity 'v', the detector moves toward the source at that speed, and this shortens the elapsed travel time for the neutrino in the satellite's reference frame.

If the GPS satellite is moving at speed 'v', the detector is moving toward it at speed 'v', the source is moving away from it at speed 'v', and the neutrino itself is moving apparently slower by 'v'. The net flight time measured for the neutrino in this frame will be the same as in the LNGS/CERN frame (except for relativistic corrections). The neutrino leaving CERN (e1) and being detected at LNGS (e2) are two time-events. The interval between these events is the same in all time-frames, when special-relativistic considerations do not apply. A special relativistic correction at a speed of 4Km/s (about 1.3/100000ths of light) cannot possibly amount to 20 ppm. Ajoykt (talk)

Please note - the criterion is verifiability, not truth. Though I agree this argument doesn't seem plausible, we are not editors of a scientific journal. MIT's Technology Review is certainly a reputable source on this subject, and if someone wants add the reference to this paper back in, there should not be anything wrong with that.--90.184.154.70 (talk) 21:23, 15 October 2011 (UTC)

MIT Technology Review is not a reliable source for fundamental physics papers. It is a newsletter, independent of the University, on latest technology issues. The problem is physicists may think the mistake in the objection so obvious they may not bother to refute it on arxiv or elsewhere. The "Contaldi" clock synchronization preprint stayed around for almost a month and was quoted and re-quoted in many articles before somebody published a scathing rebuttal (arXiv:1110.2909); the objection was known to be wrong well before that. Ajoykt (talk) 22:41, 15 October 2011 (UTC)

Newsletters counts as a reliable source. We have no business vetting papers based on whether they are "obvious mistakes" or not.--90.184.154.70 (talk) 01:47, 16 October 2011 (UTC)

That link has more on what kind of newsletter-blogs count as reliable. Here we have somebody who calls himself KentuckyFC (in other words, unsigned), reposting material from arxive.org. We don't know whether the blog is vetted by the editors. It is a news outlet reposting what is interesting on arxiv.org. How is this a credible source? We are not talking of a 'paper' here; we are talking of a posting to arxiv.org. Anybody can post there, as long as names are not hidden. Ajoykt (talk) 02:37, 16 October 2011 (UTC)

KFC used to post on this blog in his native dialect. Count Iblis (talk) 03:27, 16 October 2011 (UTC)

I've dropped the KFC source and added two other ones.--90.184.154.70 (talk) 03:33, 16 October 2011 (UTC)

Agree with Ajoykt. Regardless of quality, plausibility and the fact that it's verifiable. This is not a paper, it has not been reviewed and therefore it has the same status as numerous other blogs/postings on this subject. Those aren't mentioned, why should this one be? Putting this in the article distracts visitors from the simple fact that should be communicated in the article: There is no scientific explanation for the observed anomaly. --Unsigned comment by User:131.155.81.156

That is certainly not a fact! In all likelihood there is a scientific explanation, likely a mundane one too. That you assume there is none just goes to show why it is so important that we stick to WP:V instead of our own conceptions of The Truth.--90.184.154.70 (talk) 02:57, 18 October 2011 (UTC)

The sentence "There is no scientific explanation . . . " can be interpreted two different ways: "There is, as of this moment, no scientific explanation . . ." or "There is, and will never be, a scientific explanation . . ." You are reading the meaning in the second sense. I agree with the meaning in the first sense. --Ajoykt (talk) 04:48, 19 October 2011 (UTC)

If you can verify that "There is, as of this moment, no scientific explanation..." then the way to "communicate" this is to write it explicitly in the article along with proper citations - not to withhold other verifiable information as to leave a particular impression that may or may not be true.--83.89.0.118 (talk) 05:02, 19 October 2011 (UTC)

Of course the intended meaning was "no scientific explanation as of this moment". Obviously there is no way to back that statement with a citation. The whole point is that there is no reliable source to cite from. At this moment. But let's return to the subject. The work by Van Elburg cannot be considered a reliable source because it has not been peer-reviewed, let alone been published in a scientific journal. If it's anything, it is original research. — Preceding unsigned comment added by 131.155.81.156 (talk) 13:09, 19 October 2011 (UTC)

Plenty of reliable sources has covered the van Elburg paper, including Bad Astronomy, New Scientist and Wired. Citing a reliable source is not original research.--83.89.0.118 (talk) 19:24, 19 October 2011 (UTC)

Bah, I had a similar idea, but I assumed that the synchronization is done in the rest frame of the satellite and that the Opera team had wrongly corrected for a 32 ns delay because of a software bug, a sign error will make this 64 ns instead of zero. I didn't bother to write up a preprint and submit to arXiv :( . Count Iblis (talk) 02:26, 16 October 2011 (UTC)

As a side note, GPS receivers are prepared to deal with the relativistic effects caused by Earth's gravitational field, and also by the high speed of the GPS satellites. This is detailed in the GPS ICD, and in basically all GPS textbooks (the most common, IMO, being Misra & Enge). I've seen mention of this objection before, but no mention by Van Elburg of why this correction, usually included in receiver firmware, was not already applied. I made a note of it in the section of the article, since I think most readers would be unaware of this. siafu (talk) 21:04, 17 October 2011 (UTC)

Added a ref to Misra & Enge for the skeptical. siafu (talk) 21:17, 17 October 2011 (UTC)

The following is copied from my talkpage:

Corrections in GPS

Please consider joining the feedback request service. An editor has requested comments from other editors for this discussion. This page has been added to the following list: Maths, science, and technology When discussion has ended, remove this tag and it will be removed from the list. If this page is on additional lists, they will be noted below.

Is it against the guidelines to include, in this article, a generic statement about GPS correcting for relativistic effects, when no reliable sources establish the relevance of such a statement to the subject of the article?--83.89.0.118 (talk) 05:54, 19 October 2011 (UTC)

-- Conversation began on User talk:Siafu --

Hi. You added this sentence to the OPERA neutrino anomaly article. What is the source for this claim? Thanks.--90.184.154.70 (talk) 21:14, 17 October 2011 (UTC)

I added a ref to the article to Misra & Enge, but per my talk this is in the GPS ICD, and therefore in every GPS textbook ever. siafu (talk) 21:16, 17 October 2011 (UTC)

Boldly removed the sententence from the article again. No matter how many textbooks discuss generic relativistic corrections in GPS, it is not a comment on van Elburg's particular calculation; reading it as such is a WP:SYN.--90.184.154.70 (talk) 21:36, 17 October 2011 (UTC)

I don't see how it could be seen that way. Van Elburg is claiming that this particular correction wasn't made, and that that mistake accounts for the anomalous results. It just so happens that not making this correction would be extremely unusual-- that's not synthesis, it's verifiable fact, and I can provide plenty more references if you need them-- it is, in fact, essential to make this correction in order to obtain a position solution, since 3 ns ~ 1 meter in position error. I'm going to copy this whole conversation to the article talk page, also, since we shouldn't be picking over content here out of sight of the other editors. siafu (talk) 21:41, 17 October 2011 (UTC)

Your source says that GPS makes corrections for relativistic effects. Your source does not say that GPS makes corrections for the particular effect that van Elburg refers to. In may be that you know that the effects are identical - that's great. But you are not a reliable source.--90.184.154.70 (talk) 21:50, 17 October 2011 (UTC)

My source says that GPS makes corrections for the effects cited by van Elburg; other sources are more detailed, but even the same terminology is used. Moreover, the way the article presents it now makes it seem like this is a totally unexpected error source, when the actual fact is that GPS makes relativistic corrections, and the method for doing so has been specified since the late 70's. It's not synth to point this out, since no conclusion is being drawn, all that is being made clear is that not making the corrections would be the exception, and since this is a fact that the lay reader would be almost certainly ignorant of, it should be pointed out. siafu (talk) 21:54, 17 October 2011 (UTC)

The original formulation did draw the conclusion that the effect cited by van Elburg has been corrected for. There is no verifiable evidence for this. I've tried rephrasing it to reflect that it is a general statement about GPS, not about van Elburg's particular calculation.--90.184.154.70 (talk) 22:04, 17 October 2011 (UTC)

The formulation now concludes the effect cited by van Elburg is corrected for in those GPS systems which follow a common, credible textbook on GPS. We don't know whether the OPERA experimenters, 160 physicists total, used a GPS receiver device which did follow the text. But if you want to add that rider to the sentence, the onus is on you to show why such a statement would be credible. Ajoykt (talk) 22:11, 17 October 2011 (UTC)

Wrong. The WP:BURDEN of evidence lies with the editor who adds or restores material, in this case User:Siafu. I tried removing the sentence, but it was readded multiple times.--90.184.154.70 (talk) 22:18, 17 October 2011 (UTC)

I think the citation proves the formulation that exists now: that the effect mentioned by van Elburg, relativistic effects from satellite velocity, is corrected for in those GPS systems which follow a common, credible textbook on GPS. I see no reason to remove that part. Ajoykt (talk) 22:27, 17 October 2011 (UTC)

Van Elburg's objection is about the relativistic correction from GPS satellite velocity; he painstakingly even derives that velocity. I cannot confirm Siafu's claim the cited book has what he says it does, but assuming that is so, yes, the citation is directly relevant to the specific relativistic concern Van Elburg expressed. I also think even otherwise the SR correction doesn't amount to 20ppm at speeds of 4km/sec, but that is a different topic. Ajoykt (talk) 21:59, 17 October 2011 (UTC)

WP:SYN has a good example illustrating why exactly this type of statement is synthesis:

"The UN's stated objective is to maintain international peace and security, but since its creation there have been 160 wars throughout the world."

Both parts of the sentence may be reliably sourced, but here they have been combined to imply that the UN has failed to maintain world peace. If no reliable source has combined the material in this way, it is original research.

Since no reliable source has combined van Elburg's calculation with your generic statement about GPS to imply that the effect van Elburg mentions has been corrected for, that implication is WP:SYN.--90.184.154.70 (talk) 22:40, 17 October 2011 (UTC)

The OPERA scientists combined the exact two things you talk of. It is there in the "Boo! Hiss! . . ." reference. Ajoykt (talk) 23:54, 17 October 2011 (UTC)

No, they have never referred to van Elburg or his calculation, so that can't be part of their combination. For User:Siafu's sentence to be valid, a reliable source literally has to go out and say something to the effect of: "I have read van Elburg's paper and the effect he mentions has been corrected for in OPERA's superluminal result." Anything less is WP:OR.--90.184.154.70 (talk) 00:07, 18 October 2011 (UTC)

The exact quote: "It's too early to say whether that's the final verdict on this story—the CERN scientists did claim to have accounted for such factors in their report." In that article "such factors" refers to the Van Elberg objection. That author thinks the combination holds, assuming OPERA people are accurate in what they say. Ajoykt (talk) 00:31, 18 October 2011 (UTC)

The OPERA scientists claimed to have accounted for factors that may or may not include the factor mentioned by van Elberg. That is undisputed. But no reliable source has claimed to have read van Elberg's paper and found that the factor he mentions is already corrected for by GPS.--90.184.154.70 (talk) 00:35, 18 October 2011 (UTC)

The sentence I included specifically avoided drawing any conclusions about van Elburg's supposition, it merely contextualized it by pointing out that it would be unusual for that to be the case. Because it would be. The UN quote is a bit of a canard here, since it shows an example of using a misleading statistic, specifically one that's incomplete, since the number of wars fought since the UN can only be useful when compared to some hypothetical number of wars that would have been fought without the UN. This is not like that at all, since it is not likely that the average reader (or, apparently, average PhD physicist) has any idea how GPS works it is not inappropriate to include a comment on that. WP:SYNTH is about synthesizing available information into a new conclusion. There is no conclusion here, just a note that normally these effects are already accounted for. For all I know, the operators of the receivers used for the OPERA experiment screwed it up and van Elburg is right... but this would be very unusual indeed. siafu (talk) 01:38, 18 October 2011 (UTC)

Also, I want to make it clear that this is not a radical revelation. The GPS ICD (i.e., the primary source) is available here, and the description of how to make the receiver-side relativistic correction is on page 106, and there is a brief discussion on page 25 of the SV-side relativistic correction. This document details the specifications of the GPS system; it is essentially the reference guide for GPS receiver designers. Every GPS textbook (i.e., the secondary source) touches on this topic, as it is an integral and essential part of how GPS works. Omitting it would be like omitting the fact that cars require working oxygen sensors to function properly-- it's not a synthesized new thought to point out that it is normally done. siafu (talk) 01:45, 18 October 2011 (UTC)

I doesn't really matter how many different ways you formulate it. No reliable source states that van Elburg's objection is accounted for by GPS. Period. A statement with no reliable sources has no place in Misplaced Pages, whether expressed or implied. Period.--90.184.154.70 (talk) 02:21, 18 October 2011 (UTC)

Which is fine, since we aren't actually saying that either. siafu (talk) 03:22, 18 October 2011 (UTC)

Okay, spelling it out: No reliable source states that " effects are corrected for in normal GPS receiver operation". Period. A statement with no reliable sources has no place in Misplaced Pages, whether express or implied.--90.184.154.70 (talk) 03:35, 18 October 2011 (UTC)

The statement inserted is reliably sourced, and does not draw the conclusion you are so very concerned about; reliable sources do indicate that relativistic effects (read: all relativistic effects; there are not some mysterious other effects being invoked here) are corrected for in normal GPS operation. Reflexive identity does not require a source. siafu (talk) 13:50, 18 October 2011 (UTC)?

"Reflexive identity does not require a source." Says who?? This is exactly the problem: you infer an identity. That's great, much progress in science is made by inferring identities. However, that is not what Misplaced Pages is for! If the identity your statement relies on has no explicit, reliable source, then it doesn't belong in Misplaced Pages. This is not about me being 'very concerned' about anything, this is simply the rules. --The Artist Formerly Known as 90.184.154.70 (talk) 00:31, 19 October 2011 (UTC)

I'm familiar with policy. I am not familiar with this idea that we cannot recognize a noun in two different places as being the same thing, especially when it is used the same way in both contexts. I add again: all relativistic effects are accounted for in normal GPS operation. This is an important point that is well-known to any engineer or scientist familiar with GPS, and not a radical new idea (it's in the ICD!). It would be dishonest to present the case as if it is somehow likely that the OPERA team "failed" to take these accounts into effect, as failing to do something implies an extra step that was just not taken. It's just not possible to just fail to do that-- the GPS receiver would have to be malfunctioning in a dramatic fashion (64 ns = 19.2 m of position error!) and this would have to go completely unnoticed. Maybe it happened, I'm not concluding that it didn't and certainly not using wikipedia's voice to do so, but the context is both important and relevant. The argument these are not the same "relativistic effects", frankly, is simply specious; if we were talking about cars, it would be WP:SYNTH to connect "cars" with "cars", or to contextualize a statement about cars to point out that they usually run on the ground, that they usually have tires, or that they usually require fuel to run. siafu (talk) 01:22, 19 October 2011 (UTC)

"... if we were talking about cars, it would be WP:SYNTH to connect 'cars' with 'cars', or to contextualize a statement about cars to point out that they usually run on the ground, that they usually have tires, or that they usually require fuel to run."   You. Are. Right. Each of those examples require sources just as much as the present one. It is not our business to "connect" anything. Misplaced Pages is not a directory of information that you and I consider to be "obvious". It is a directory of verifiable information. If that is "specious", then Misplaced Pages is "specious".--83.89.0.118 (talk) 02:21, 19 October 2011 (UTC)

But you are claiming more - you are saying to write the above statement about cars, one needs to find a source that has all three statements in one place; it is not enough to just cite separate sources for each part. Why stop that logic at sentences? Why not apply it to paras? It would then not be enough to cite sources for each sentence in a para. To avoid problems with implications, one would have to find a source that has all the sentences of the para. We can carry the argument further to sections (should be present in entirety in some citation), articles, and the whole of Misplaced Pages. The question of "implications" is subjective. There isn't much point just the three of us arguing this, since it looks our stands on the subjective part are clear. If somebody else weights in, we can revisit this. --Ajoykt (talk) 05:18, 19 October 2011 (UTC)

I am not claiming anything, I am citing the rules: "Do not combine material from multiple sources to reach or imply a conclusion not explicitly stated by any of the sources." What is implied is a matter of WP:CONSENSUS.--83.89.0.118 (talk) 05:54, 19 October 2011 (UTC)

Relativistic effects interfering with synchronization of the two distant clocks can be an issue, if the OPERA team made a mistake, or if the GPS system for clock synchronization contains a bug. Both are viable possiblilities; note that the GPS system for clock synchronization has never been tested before to this accuracy. On of the very first reactions to the OPERA results from a rival team was in fact that GPS is not reliable enough for accurate clock synchronization over large distances.

The distance measuements using GPS satellites is well established, that's not an issue. But now, you need to also know the position of one of the GPS satellites in, say, the LNGS rest frame. The signal of that GPS satellite is detected by both the LNGS and CERN clocks as a synchronization signal. Clearly, if you know where that satellite was at the moment the signal was sent according to the LNGS clock, you know when that same signal arrives at the CERN clock, according to the LNGS clock. While there is an automatic procedure for this within the GPS system, it has never been tested to within 100 ns accuracy over large distances, so one cannot exclude any bugs being in this system. Count Iblis (talk) 16:22, 19 October 2011 (UTC)

While I agree with most of your comments, it is not correct to say that the GPS timing system has not been tested to 100 ns accuracy. As I mentioned before, 3 ns is ~ 1 meter of position error, since GPS is based on lightspeed travel time delay. GPS receivers are commonly used by the geophysics, seismology, and surveying communities to accuracies down to the level of a few mm, and in order to do this very fine clock synchronization is required. Even with double differencing, an advanced technique used to eliminate clock error, a stable frequency standard is required on the satellites (they were each launched with 4 atomic clocks, some cesium, some rhubidium). I don't want to extend the claims in the article to say that van Elburg is simply wrong because of this, but it's absolutely true that he's making an extraordinary claim. siafu (talk) 18:57, 19 October 2011 (UTC)

arXiv categories

Van Elburg's paper is in the "general physics" category in arXiv. This is where the moderators dump things which are of "no plausible interest" anywhere else, including stuff that is wrong but is formatted correctly and is from somebody with some physics background. Note the main articles on OPERA are in the "High Energy Physics" category.--Ajoykt (talk) 19:38, 18 October 2011 (UTC)

Yes, but then quite a few of the HEP-PH papers are also wrong, even some writtten by big experts. Take e.g. this paper. I was planning to this paper for a homework assignment asking students to explain where they went wrong, but unfortunately this spoilsport paper appeared  :( . Count Iblis (talk) 20:22, 18 October 2011 (UTC)

This section on an unverified claim should be deleted as it is based upon a complete misunderstanding of the experimental set up. In other words the claim is based upon a failure to correctly understand the experiment and how it was performed. Upon reading the paper it is clear that it is simply nonsense and doesn't deserve to be cited on Misplaced Pages. --72.64.36.237 (talk) 15:33, 19 October 2011 (UTC)

If you can find more than one WP:RELIABLE source to back that up, I am not opposed to deleting the section. But until then, it is not our place to judge.--83.89.0.118 (talk) 19:28, 19 October 2011 (UTC)

The ICARUS negative on Cohen-Glashow emissions

Hmmm, ICARUS is claiming the OPERA results are wrong, without even bothering to measure the speed of neutrinos. They assume the C-G theory (though it has no experimental backing since no one has ever seen anything superluminal, other than OPERA), and then they declare neutrinos have got to go well below the speed OPERA reports. I guess we will now have a rash of media reports writing off the OPERA results. Ajoykt (talk) 03:29, 18 October 2011 (UTC)

To be fair, they only seem to be saying that their results "refute a superluminal interpretation of the OPERA result according to the Cohen and Glashow prediction". I.e. they only refute the OPERA result to the extent that C-G theory is right.--90.184.154.70 (talk) 04:17, 18 October 2011 (UTC)

They claim a smaller (stricter) value for 'delta' for the CNGS beam. Since delta is the excess velocity for neutrino over light, that is effectively claiming CNGS neutrinos go slower than light (or at least no faster than 40 parts in a billion). This part of their claim is not qualified by C&G's theory being right. They consistently use the word "must": "superluminal charge-less neutrinos must emit radiation," "these analogs to must appear," They also use words like "hereby alleged anomaly" to refer to the OPERA result. Ajoykt (talk) 04:27, 18 October 2011 (UTC)

It is misleading to say that there is no experimental support for C-G theory. Thing is that there exists a successful Standard Model (extended to take into account finite neutrino masses and mixings). The interactions with particles and neutrinos are correctly described by this model, where precision tests are possible, the agreement with theory and experiment is phenomenal.

The prediction that superluminal neutrinos must emit Cherencov radiation is then almost proven. The Standard Model Lagrangian is, after all, what you are left with if you were to integrate out the unkown high energy physics. So whatever you postulate of what lies beyond the Standard Model, as far as low energy physics is concerned, you must end up with the known Standard Model, otherwise you would fail to predict what we already know to be true.

This then means that you can only add to the Lagrangian tiny renormalizable terms allowing for Lorenz invariance breaking. The amplitude for Cherenkov radiation production is then largely determined by the known terms in the Lagrangian, the tiny terms only allow the neutrinos to travel faster than light, but they don't contribute to the radiation to leading order. To prevent Cherenkov radiation from being emitted, you must somehow make the effect for the tiny terms very large, but that is impossible. You therefore would have to assume that these terms aren't tiny at all but then that would mess up the correct predictions of the Standard Model. So, you need to add more terms to make sure all the known predictions are correct and yet that neutrinos don't emit Cherenkov radiation.

But doing that would amount to postulating a brand new theory without any experimental evidence at all, other than the assumption that the OPERA results are correct. The C-G theory, in contrast, is what you would expect based on current knowledge. Count Iblis (talk) 15:48, 18 October 2011 (UTC)

Predictions are proven by experiments, not by the confidence levels of theorists. The C-G theory is unproven. After all, more than a century ago, that clocks should tick at the same rate in every frame was also "almost proven." The point is one can refute an experimental result only by pointing out what is concretely wrong with it, or by trying to, and failing to, replicate the results. The entire C-G exercise seems only to prove how more radical a change the OPERA results, if true, presage for existing physics. That fact cannot refute the experiment itself. I am not saying OPERA results are right, but the ICARUS result is no refutation, despite their wording. Wording we have to include in Misplaced Pages. Ajoykt (talk) 15:57, 18 October 2011 (UTC)

But note that Einstein developed relativity based on the, at that time, known experimental knowledge, no one had ever observed time dilation. His theory was well accepted long before rigorous and precise tests of relativity were available, simply because it offered a much better explanation for known facts.

So, I would say that if OPERA is proven correct, that would be similar to experimental tests of special relativity falsifying it against all expectations, and eventually proving correct the old fashioned aether theory. Count Iblis (talk) 16:31, 18 October 2011 (UTC)

I completely agree with Ajoykt. What you, I and the ICARUS experiment "would say" is completely irrelevant. Until OPERA produces a slower-than-light result, nothing has been refuted.--83.89.0.118 (talk) 01:13, 19 October 2011 (UTC)

B.t.w., you can, of course, criticise the ICARUS measurement of neutrino speed for making asummptions that are "in small print" about assuming a that a certain aspect of the theory is correct, but in practice all measurements depend on assuming some theory. In case of null results that is used to rule out new physics, this is obviously potentially a big problem. Compare e.g. the experimental results that are used to set limits to the mass and charge of the photon. They obviously depend on assuming a theory that describes the properties of massive or charged photons in a sensitive way, as pointed out here w.r.t. massive photons and for the charge of the photon, there isn't a consistent theory at all.

What makes the case of superluminal neutrinos different is that the Cherenkov radiation depends primarily on the known terms in the Standard Model Lagrangian, so it's to a high degree model independent. Count Iblis (talk) 17:24, 18 October 2011 (UTC)

If OPERA is proven right, it would be just like Michelson-Morley. A new theory which has the old theory as its limit or special case would be needed. C&G haven't proven such theories are impossible - they have ruled out only a specific set. My core objection is to the claim these things "refute" the OPERA experiment. They don't. I don't know why the papers use that word. Theories don't refute experiments. ICARUS, though an experimental result, doesn't refute OPERA. Yes, all measurements depend on some theory. But if we already have a measurement in place, we can't refute that measurement by measuring something else hypothesized to correlate. A hypothesis very elegant, plausible and theoretically strong, but since it gets into faster-than-light territory, not proven. Ajoykt (talk) 18:07, 18 October 2011 (UTC)

As expected, blogoland has lit up with fireworks celebrating the demise of the OPERA superluminal result. Our article needs to stay more neutral than that. The anomaly is still an anomaly, and looks likely to stay that way till late next year, when new data from TK-2 and MINOS would be out; if there is a systematic error, it is likely so subtle we may not catch it. The "reinterpretation" of existing data from MINOS, expected in 4 months, probably would just reiterate their previous conclusion - not enough accuracy to be sure. Ajoykt (talk) —Preceding undated comment added 18:23, 18 October 2011 (UTC).

Title

The use of the word anomaly is invalid here. There is no anomaly. It is a properly performed experiment. The fact that the result doesn't fit the kind of result that the physics community wants is not relevant. The result is what it is. The proper title should reflect the actual result which was that the measurement showed that the measured neutrino TOF was less than the calculated TOF for light waves in a vacuum.72.64.36.237 (talk) 15:39, 19 October 2011 (UTC)

I think what you must not know what an anomaly is. Both the OPERA team itself, as well as secondary sources (including Cohen-Glashow, whose paper is the only one currently accepted for peer review), refers to it as an anomaly. Here, the word of a Nobel laurate has greater weight than yours or mine.--83.89.0.118 (talk) 20:12, 19 October 2011 (UTC)

Secondary sources

Regarding arXiv-preprints in general: Including non-peer reviewed primary sources, without peer reviewed primary or secondary sources, is problematic in the light of WP:Notable, WP:Secondary, WP:Undue, WP:OR and WP:SYNTH. Now I'v looked through some (science, nature, newscientist etc.) secondary sources given in the article, and searched for references to the arxiv-preprints currently included in our article. Here is the result:

• Cited: Coleman&Glashow: arXiv:1109.6562, Icarus: arXiv:1110.3763, Elburg: arXiv:1110.2685.
• Not cited: Ehrlich: arXiv:1110.0736, Broda: arXiv:1110.0644, Alicki: arXiv:1109.5727, Winter: arXiv:1110.0424

That doesn't mean that I agree or disagree with those articles, but without secondary source there is no sufficient justification to include the non-cited papers here.--D.H (talk) 19:44, 19 October 2011 (UTC)

Though I think each of those papers add valuable information, I have to agree with you on a principal level - the references to them should probably be removed for now.--83.89.0.118 (talk) 20:02, 19 October 2011 (UTC)

Done. --D.H (talk) 20:23, 19 October 2011 (UTC)

Mark what needs secondary sources. Don't arbitrarily remove stuff. It takes time to dig up the secondary sources. They do exist. Ajoykt (talk) 20:31, 19 October 2011 (UTC)

Thanks for your effort, Ajoykt. It seems that only the Ehrlich-Ref is still missing. PS: I now see, that "83.89.0.118" marked them. --D.H (talk) 20:49, 19 October 2011 (UTC)

The secondary source for Erhlich seems a bit dubious. It looks like a personal homepage, only hosted at MIT.--83.89.0.118 (talk) 20:59, 19 October 2011 (UTC)

Note on sources

The Cohen/Glashow paper will be published in Physical Review Letters. See newscientis, and PRL. --D.H (talk) 15:19, 19 October 2011 (UTC)

Good catch. I was a bit incredulous that this would get published so soon.--Louiedog (talk) 15:28, 19 October 2011 (UTC)

I could be wrong, but in the "Energy decay through pair bremsstrahlung" section, shouldn't the stated 40 ppb value be 0.4 ppb? 91.155.92.202 (talk) 19:14, 19 October 2011 (UTC)

${\displaystyle \delta =4\times 10^{-8}=0.00000004=40/1000000000}$. --D.H (talk) 20:13, 19 October 2011 (UTC)

Merge

So far I think we can merge the OPERA neutrino anomaly here until at least one independent confirmation of the finding. Before an independent verification the issue seems to remain within the OPERA experimental framework. Ehud (talk) 21:08, 19 October 2011 (UTC)

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