CERN team claims measurement of neutrino speed >c

[PAllen]

Also, the following thread, where Parlyne gave me a basic mathematical derivations:

https://www.physicsforums.com/showthread.php?p=3271891&highlight=oscillation#post3271891

 

[DevilsAvocado]

But I still on the skeptical side

Me too, skepticism is the safest route.

Though I would love if this was true = exciting times! But most probably it’s wrong. And if it finally turns out to be right, it probably doesn’t mean what we now think it means... too much empirical data supports Einstein.

But sometimes I’m even skeptical to what I just wrote... who knows...

(not me anyway)

 

[DevilsAvocado]

Also, the following thread, where Parlyne gave me a basic mathematical derivations:

Wow... this is only the basics... now I know why I should stick to assembler = nice and short lines...

Parlyne is real pro, isn’t he?

 

[G. E. Hunter]

Einstein would be happy to see our new scientists proving him wrong - he would love to see progress and new results showing C is just the limit for light suggesting other particles may have faster speed limits. So this is two confirmed tests. Time for more - where else can they test this? Interested to see where this leads.

 

[Hans66]

Hi all, I have a question. One of the arguments being used against neutrinos traveling faster than light is the absence (or non-detection) of Cherenkov radiation. AFAIK, Cherenkov radiation relates only to particles with a charge.
Can anyone explain this to a relative physical ignoramus? Thanks in advance.

 

[PatrickPowers]

Hi all, I have a question. One of the arguments being used against neutrinos traveling faster than light is the absence (or non-detection) of Cherenkov radiation. AFAIK, Cherenkov radiation relates only to particles with a charge.
Can anyone explain this to a relative physical ignoramus? Thanks in advance.

It's Cherenkov-like radiation: similar but not the same. I don't understand it. It's been discussed in the forum already, so you could search for it.

 

[lalbatros]

Hi all, I have a question. One of the arguments being used against neutrinos traveling faster than light is the absence (or non-detection) of Cherenkov radiation. AFAIK, Cherenkov radiation relates only to particles with a charge.
Can anyone explain this to a relative physical ignoramus? Thanks in advance.

This is a theoritical argument against an experimental result.
Basically this is nonsense.
A bit like saying the experiment is wrong since we know FTL is impossible.

However, we can also consider that this paper about Cherenkov radiation reminds us that, if the experimental result is confirmed there will be cracks elsewhere in theoretical physics. From there, it is all a question of likelyhood (or belief): if you consider the neutrino-Cherenkov section of theoretical physics as very robust, then you might decrease your belief in the OPERA result.

In other words: this kind of argument is useful to chose the topics you will spend your time on. Using such "likelyhood" point of view, you may avoid losing your time or wasting your career. However, it doesn't prove anything.

Personally, I give little chance for the OPERA result to stand the long run. I strongly believe there is a bug somewhere.
Nevertheless, my belief against the OPERA result has decreased somewhat because of section 9 in their last paper. The high time resolution data (almost) completely void any statistical criticism.
The bad news is that the rest of the scrutiny will be much more difficult. Checking the clock synchronization and the distance measurement might be a much more difficult task. Fortunately, it is now more and more likeky that the outcome will be very interresting, if at least for learning something new about clocks and distances.

My belief has changed so much, that I now even spend some time to dream about some FTL physics.
Yet I still favor an experimental difficulty.

 

[TrickyDicky]

In the preprint a 25ns jitter of the GPS clock is mentioned to justify the 50ns spread in the neutrinos delta times, but I'd think that would also produce some gaussianity in the fig. 18 plot which is not observed.

 

[DevilsAvocado]

Einstein would be happy to see our new scientists proving him wrong

Probably you’re right, this is not the first time... once there was "Hundred authors against Einstein" and his reply was amusing and powerful:

"If I were wrong, it would only have taken one."​

However the 160 researchers in the OPERA team are not stupid (as the "Hundred authors"), they have never claimed that Einstein was wrong.

Nevertheless, Einstein would probably have enjoyed the current research, but surely he would not have appreciated some of the ignorant comments in this thread.

 

[Aether]

Hi all, I have a question. One of the arguments being used against neutrinos traveling faster than light is the absence (or non-detection) of Cherenkov radiation. AFAIK, Cherenkov radiation relates only to particles with a charge.
Can anyone explain this to a relative physical ignoramus? Thanks in advance.

The idea is that if neutrinos can move faster than the maximum attainable velocity of electrons (and positrons), then neutrinos should rapidly decay into electron-positron pairs when they exceed the ultimate speed limit for electrons and/or positrons.

For example: if neutrinos can move faster than light, but electrons and/or positrons can't, then such neutrinos should rapidly decay into electron-positron pairs. This was clearly not observed by either OPERA or ICARUS, so: either the neutrinos that were detected were not moving faster than light, or electrons and/or positrons can also move faster than light when they are emitted by neutrinos that are moving faster than light.

If the neutrinos detected by OPERA really were moving faster than light, then electrons and/or positrons must also be able to move faster than light, and some people have suggested that we should be able to observe vacuum Cherenkov radiation from these charged particles moving faster than light in space; which is not known to have ever been observed. Such a suggestion seems to implicitly assume the existence of a luminiferous aether (note that I am not the one who made this suggestion in the first place) since the only known mechanism for Cherenkov radiation involves an interaction between charged particles traveling through a physical transmission medium for light.

 

[Hobin]

Nevertheless, Einstein would probably have enjoyed the current research, but surely he would not have appreciated some of the ignorant comments in this thread.

I disagree. Einstein was one of those smart people who nevertheless knew how little he knew. If he saw an ignorant comment, I think it would be more likely he would appreciate it as an opportunity to teach that person something new.

Ignorance is no fault, per se. Denial of the facts is.

 

[DevilsAvocado]

I disagree. Einstein was one of those smart people who nevertheless knew how little he knew. If he saw an ignorant comment, I think it would be more likely he would appreciate it as an opportunity to teach that person something new.

Ignorance is no fault, per se. Denial of the facts is.

There you go. Call it what you want, but I’m 100% that Einstein would not have appreciated that some users continue to argue that the OPERA team are claiming new physics and/or that Einstein was wrong.

This is distortion, denial, ignorance, or whatever, of the facts.

 

[hefty]

Personally I think that it's MUCH MORE easier to believe that We, humans, are still FAR AWAY to be done with understanding all the aspects of the Universe, than, that We currently know everything (on this particular topic a others).

i.e.: Galileo --> Newton --> Einstein --> (New, closer to reality, physics)

When Newton proposed his laws of Gravity, the dynamics of Mercury (not Freddy, the Planet) were not fully known.
When they finally were known better, We, humans, started to think that there was something missing with Newton's law's of movement.
Einstein's General Relativity solved it.

Now, We're probably in the same crisis... And when this experiment is confirmed, We, humans, will start to know that there is something missing, probably very small, in Einstein's Relativity.But to assume that every thing in Relativity matches to perfection the reality of things, is much more difficult than to think otherwise.

 

[DevilsAvocado]

... But to assume that every thing in Relativity matches to perfection the reality of things, is much more difficult than to think otherwise.

This is correct. Any physical theory is always provisional; you can never prove it.

But another fact about physical theories is that a new theory is supposed to incorporate previous theories, and not refute empirical facts.

What we are dealing with here, is almost as if someone would claim a brand new theory where Newton’s apple from now on will suspend itself in mid-air, and Freddy Mercury will arise from the dead and start walking on water...

That’s why the OPERA team is very careful with what they say, and don’t say.

 

[hefty]

This is correct. Any physical theory is always provisional; you can never prove it.

But another fact about physical theories is that a new theory is supposed to incorporate previous theories, and not refute empirical facts.

What we are dealing with here, is almost as if someone would claim a brand new theory where Newton’s apple from now on will suspend itself in mid-air, and Freddy Mercury will arise from the dead and start walking on water...

That’s why the OPERA team is very careful with what they say, and don’t say.

:-)

Regarding the part in red, I think I missed something if in fact We already have a new physical theory that is not including previous theories. We're far from that point, I think.

What We do have right now (hopefully to make it more interesting) is a new empirical fact that contradicts previous measures of something.

This is the same as what happened before, when Freddy Mercury(It was him right?) did some better and more precise observations of Planet Mercury, and concluded that the orbit times were not matching predictions from Newtonian Mechanics.

Later, Albert Einstein came to give a new, better theory that included Newtonian Mechanics, and also explained the movements of Freddy Mercury. (I mean, Planet Mercury) :-)

Hopefully there is another human mind like Einsteins' among us, that is working hard to include Relativity in a New and better Theory that also explains new empirical facts like FTL Neutrinos.

 

[DevilsAvocado]

... new empirical facts like FTL Neutrinos.

Well, I think you are just a 'little' bit too optimistic about what constitutes empirical facts.

 

[hefty]

Well, I think you are just a 'little' bit too optimistic about what constitutes empirical facts.

No, I'm not... You just quoted me in the wrong place :-)

hefty said too:
What We do have right now (hopefully to make it more interesting) is a new empirical fact that contradicts previous measures of something.


But anyway, you agree that CERN-GS measurements are not even close to leave Relativity outside of a new plausibly theory, right? They haven't provided any new theory yet.
They are just giving us new empirical facts (once confirmed by independent sources)

 

[DevilsAvocado]

They are just giving us new empirical facts (once confirmed by independent sources)

THE LAW OF ENTHUSIASTIC LAYMEN:

§1 Ye shall not play the Mercury song "We Are The Champions", before the fat lady sings, or Ye shall make a fool of Yourself.​

 

[danR]

Given the complexity of measurement variables that must be rigorously analyzed and accounted for, I think some people will not be satisfied until 1 meter packets of neutrinos and photons have a foot-race down a 10 kilometer evacuated tube enough times to declare a consistent winner or else a consistent dead heat.

Regrettably, I must be one that needs that rather time and money expensive method.

(And for the record, I can't buy the 'must be Cherenkov radiation' argument. Or any such second-order reasoning. I would always have the suspicion, 'well, if FTL neutrinos just happen to exist, contrary to c=maximum, then perhaps they would be trivially guilty of a lesser crime of Cherenkov-emission evasion.')

 

[hefty]

THE LAW OF ENTHUSIASTIC LAYMEN:

§1 Ye shall not play the Mercury song "We Are The Champions", before the fat lady sings, or Ye shall make a fool of Yourself.​

I don't think they are singing "We are the Champions". They are showing lot of carefulness on their papers.

But, since it seems it was not clear enough, what I was clearly stating is that this comment of yours was wrong:

But another fact about physical theories is that a new theory is supposed to incorporate previous theories, and not refute empirical facts.

In your comment you were giving the status of "Physical Theory" to just a "plausibly-to-be-confirmed-by-independent-sources" Empirical Fact.

 

[Hobin]

There you go. Call it what you want, but I’m 100% that Einstein would not have appreciated that some users continue to argue that the OPERA team are claiming new physics and/or that Einstein was wrong.

This is distortion, denial, ignorance, or whatever, of the facts.

I quite agree. But you seem to be arguing against a straw man. I did not say anything about the OPERA team, I was merely saying what I think Einstein would be likely to think.

Also, you seemed to have missed the difference I was trying to point out. This is exactly what I called the difference between ignorance and denial. Ignorant are those who do not know what the OPERA team claims, and will be happy to change their views when we tell them. Those who are in denial are the ones who do not know what the OPERA team claims, yet insist that they must claim X.

 

[cbetanco]

FTL neutrinos can be incorporated into existing theories like the Extended Standard Model (ESM), in which both CPT and Lorentz invariance are violated by spontaneous symmetry breaking. This does not contradict current theories, as observer Lorentz transformations (rotations and boosts) are still an invariance of the model and any CPT violating terms are highly suppressed with a factor of 1/M, where M is the Planck mass. The minimal standard model is recovered in the appropriate limit. The ESM is both renormalizable and preserves the usual global U(1) gauge invariance.

Even though the OPERA results might not pass the test of time, it is worth noting that there are fully consistent theories out there that can incorporate FTL neutrinos, and we shouldn't downright dismiss the idea of FTL travel as a possibility.

 

[DevilsAvocado]

I quite agree. But you seem to be arguing against a straw man. I did not say anything about the OPERA team, I was merely saying what I think Einstein would be likely to think.

Also, you seemed to have missed the difference I was trying to point out. This is exactly what I called the difference between ignorance and denial. Ignorant are those who do not know what the OPERA team claims, and will be happy to change their views when we tell them. Those who are in denial are the ones who do not know what the OPERA team claims, yet insist that they must claim X.

Well, I know I’m not drunk, but I can’t pledge for others in this thread... this is the most bewildering gibberish I’ve seen in a long time... okay, that was not nice, I change my mind – it’s hilarious.

*Ignorant* are those *who do not know* what the OPERA team claims, and will be happy to change their views when we tell them.

Those who are in *denial* are the ones *who do not know* what the OPERA team claims, yet insist that they must claim X.​

Look, we have not only a problem in understanding physics, basic logic, but also plain English. If you look at what your friend has produced in the last posts, it’s clear that he can’t even handle personal pronouns.

I’m afraid I can’t help you guys with this. I don’t have the time. My only friendly recommendation is to first make sure you understand what has been said, and then deploy your advanced speculations, of course within the rules of PF.

That’s all I can do! Take care, be good, and remember – PF Mentors are online 24/7!


P.S. Okay, one last time, in case you guys did miss it:

Exactly, blame the people who don’t understand plain English:

Dario Autiero @3:33

– We have chosen not to interpret our results in terms of new physics.


https://www.youtube.com/watch?v=AN9IQyHzk90​

Not the OPERA team.

More verbosely, from page 29 of the revised OPERA preprint that has been linked to already:

In conclusion, despite the large significance of the measurement reported here and the robustness of the analysis, the potentially great impact of the result motivates the continuation of our studies in order to investigate possible still unknown systematic effects that could explain the observed anomaly. We deliberately do not attempt any theoretical or phenomenological interpretation of the results.

("Significance" in this context surely refers to "statistical significance" rather than to "impact" on fundamental physics.)

 

[Hobin]

*Ignorant* are those *who do not know* what the OPERA team claims, and will be happy to change their views when we tell them.

Those who are in *denial* are the ones *who do not know* what the OPERA team claims, yet insist that they must claim X.

You bolded the wrong words. You should've bolded 'will be happy to change their views when we tell them' and 'yet insist that they must claim X'.

I repeat, I have never made any claim about what the OPERA team is or is not saying, I didn't even read much about it. Therefore, I am ignorant by definition. Yes, I do know that the OPERA team has chosen not to interpret the results in terms of new physics (and that it's wise for people without advanced knowledge in the field not to try to do better). But no, I don't know much about neutrino's, and have other things to do with my time (not suggesting that this isn't important, obviously, just not important *to me*)

Quite simply, my post never even touched the subject of physics itself. However, what I was trying to do was point out what I thought was the difference between ignorance and denial, and why I thought someone like Einstein would have little problem with ignorance in itself, but very much with denial.

If you recall, this was my first comment in this thread:

Nevertheless, Einstein would probably have enjoyed the current research, but surely he would not have appreciated some of the ignorant comments in this thread.

I disagree. Einstein was one of those smart people who nevertheless knew how little he knew. If he saw an ignorant comment, I think it would be more likely he would appreciate it as an opportunity to teach that person something new.

Ignorance is no fault, per se. Denial of the facts is.

Thus, you can see that I was trying to point out what I would consider a difference between ignorance and denial. I wasn't trying to say that some comments in this thread were neither of those. What I hoped would be a quick comment turns out to get this completely of track, which had not been my intention. I admit that I would have been wiser not to state so boldly "I disagree" in that comment, as it suggests that I think some of what you call ignorant comments, aren't ignorant. (Which I don't really *know*. After all, like I said, I have very little knowledge in this area.)

Also, I do not think there's any reason to be this derogatory.

 

[BertMorrien]

The newest outcome of Opera's neutrino velocity measurement included also the result of an alternative analysis.
This result was compatible with the earlier finding, and so was the result of a new experiment with much shorter pulses.
This means, Opera’s current analysis must be valid.
This means also that Opera knew exactly what they were doing.
Consequently, the PDF obtained by summing the PEWs is valid, despite the lack of PEW parts with a corresponding event.
This is because with enough events, the event distribution resembles the shape of the PDF sufficiently for trusting the outcome of a maximum likelihood analysis.
It is regrettable that this point never became clear to me before.

The lesson learned is that declaring the PDF and Opera’s analysis invalid is a good example of narrow minded reasoning; a humble apology is in order here.

Bert

 

[ZapperZ]

If this thread will degenerate into "you shouldn't say that" and "no, I didn't" and "yes you did", then it will imply that the important and on-topic physics discussion has been exhausted, and this topic should be closed. You guys decide on the fate of this discussion (and this thread) if you want to continue along this line.

Either we get back to discussing physics and stay on-topic, or this will end.

Zz.

 

[danR]

If this thread will degenerate into "you shouldn't say that" and "no, I didn't" and "yes you did", then it will imply that the important and on-topic physics discussion has been exhausted, and this topic should be closed. You guys decide on the fate of this discussion (and this thread) if you want to continue along this line.

Either we get back to discussing physics and stay on-topic, or this will end.

Zz.

Well, I tried to offer something a little more physics-wise (supra) but nobody seemed to notice. So I guess this thread's come to an end. I would have thought the new result would have re-started this thread.

 

[Orion1]

In a paper posted on the same website as the OPERA results, the ICARUS team says their findings "refute a superluminal (faster than light) interpretation of the OPERA result."

ICARUS did not detect any Cherenkov radiation.
[/Color]
Reference:
http://arxiv.org/ftp/arxiv/papers/1110/1110.3763.pdf"

 

[Protonium]

CERN once again confirm that neutrino is faster than light ??

 

[OnlyMe]

CERN once again confirm that neutrino is faster than light ??

Yup. Here is a link to the arxiv preprint, Measurement of the neutrino velocity with the OPERA detector in the CNGS beam*.

They ran the experiment with far shorter neutrino pulses and came up with results consistent with the earlier data.

I think from earlier information this was intended as a proof of concept, with the intent to run a more complete experiment early next year.

I haven't finished reading the paper yet, it takes me some time these days.