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Australia6232 Posts
On October 20 2011 17:52 Umpteen wrote:Show nested quote +On October 20 2011 17:04 Belisarius wrote:EDIT: it's this guy, and this article, and it doesn't seem like the CERN scientists have confirmed or even responded to what he said. At this stage the 'explanation' is just him going: "Did ya remember to correct for this?" No: he's actually quoting their paper and pointing out that they aren't correcting for it: Show nested quote +The authors of the OPERA paper [5] seem to include a correction for the Lorentz transformations,
but they do not explicitly correct for detector movement in the satellite refrence frame. As they
project the time provided by the satellite’s clock back to the baseline, they seem to assume incorrectly that the outcome of their experiment should be equivalent to the time of flight τb using a
clock in the baseline reference system:
<equation quoted from original paper>
In fact, however, they should observe the Lorentz transformation-corrected time of flight as measured in the satellite reference system, i.e.:
<corrected equation>
Edit: On the other hand the second correction he applies does assume something not explicitly presented in the original paper - sorry about that.
Yeah, sure. My point is really.... I mean, van Elburg is certainly legitimate and I wouldn't be surprised if he's worked it out, but until the CERN guys back down or the general community stands behind him, I won't be considering it "debunked."
Plus. anyone using "seems" that many times in one paragraph talking about someone else's work generally doesn't have the full story at their disposal.
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On October 20 2011 18:19 Belisarius wrote:Show nested quote +On October 20 2011 17:52 Umpteen wrote:On October 20 2011 17:04 Belisarius wrote:EDIT: it's this guy, and this article, and it doesn't seem like the CERN scientists have confirmed or even responded to what he said. At this stage the 'explanation' is just him going: "Did ya remember to correct for this?" No: he's actually quoting their paper and pointing out that they aren't correcting for it: The authors of the OPERA paper [5] seem to include a correction for the Lorentz transformations,
but they do not explicitly correct for detector movement in the satellite refrence frame. As they
project the time provided by the satellite’s clock back to the baseline, they seem to assume incorrectly that the outcome of their experiment should be equivalent to the time of flight τb using a
clock in the baseline reference system:
<equation quoted from original paper>
In fact, however, they should observe the Lorentz transformation-corrected time of flight as measured in the satellite reference system, i.e.:
<corrected equation>
Edit: On the other hand the second correction he applies does assume something not explicitly presented in the original paper - sorry about that. Yeah, sure. My point is really.... I mean, van Elburg is certainly legitimate and I wouldn't be surprised if he's worked it out, but until the CERN guys back down or the general community stands behind him, I won't be considering it "debunked." Plus. anyone using "seems" that many times in one paragraph talking about someone else's work generally doesn't have the full story at their disposal.
Fair points - but I think the fact the calculated correction exactly matches the anomalous results is highly suggestive.
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United States24709 Posts
Just as I expected it was an error on the part of the researchers, but... I can't believe they forgot to take into account for relativistic simultaneity lol
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I am highly skeptical that the van Elburg explanation for the error is correct, for several reasons.
1) GPS tick has the ephemeris of the satellite in it, you would use this for the common-view for synchronizing clocks, not your own calculation for the position of the satellite. This would eliminate this error already on the GPS system level. Note that the actual time the GPS clock gives you is completely irrelevant to OPERA, they only use the GPS tick as the common event to synchronize the clocks by.
2) The clock synchronization was independently checked to be accurate by 2 different metrological organizations. Such an error would immediately be caught here.
3) The error would not be consistent, it would depend on the speed and direction of the GPS satellite the clocks were synchronized with.
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On October 21 2011 20:19 sulliwan wrote:
I am highly skeptical that the van Elburg explanation for the error is correct, for several reasons.
1) GPS tick has the ephemeris of the satellite in it, you would use this for the common-view for synchronizing clocks, not your own calculation for the position of the satellite. This would eliminate this error already on the GPS system level. Note that the actual time the GPS clock gives you is completely irrelevant to OPERA, they only use the GPS tick as the common event to synchronize the clocks by.
2) The clock synchronization was independently checked to be accurate by 2 different metrological organizations. Such an error would immediately be caught here.
3) The error would not be consistent, it would depend on the speed and direction of the GPS satellite the clocks were synchronized with.
Afaik OPERA answered that van Elburg did not understand how GPS includes special relativity, I doubt his explanation is valid.
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On October 23 2011 01:45 Maenander wrote:Show nested quote +On October 21 2011 20:19 sulliwan wrote:
I am highly skeptical that the van Elburg explanation for the error is correct, for several reasons.
1) GPS tick has the ephemeris of the satellite in it, you would use this for the common-view for synchronizing clocks, not your own calculation for the position of the satellite. This would eliminate this error already on the GPS system level. Note that the actual time the GPS clock gives you is completely irrelevant to OPERA, they only use the GPS tick as the common event to synchronize the clocks by.
2) The clock synchronization was independently checked to be accurate by 2 different metrological organizations. Such an error would immediately be caught here.
3) The error would not be consistent, it would depend on the speed and direction of the GPS satellite the clocks were synchronized with. Afaik OPERA answered that van Elburg did not understand how GPS includes special relativity, I doubt his explanation is valid.
I'll quote myself:
Another issue is that you need atleast 4 GPS satellites for a reading and more for a more precise reading so I find it difficult to take his argument seriously because he's blaming it all on one satellite. So now you're talking about the motions of 4+ satellites all in different orbits, all with different relative motions to the sender and receiver at different times.
The author of the paper assumed GPS only used a single GPS satellite. GPS uses a minimum of 4 to triangulate a 3d position (3 to get position on surface of earth but not height). There are over 20 GPS satellites that depending on time of day that a receiver can talk to. You're going to be connecting to different ones depending on lines of sight, weather, where the satellites are in orbit. You also usually need to receive more than 4 for higher accuracy. So you can't blame it on 1 satellite not to mention the equipment auto compensates for this because they compensate for Special Relativity.
So basically this is why they are running more experiments on this for a few weeks:
http://www.newscientist.com/article/dn21093-fasterthanlight-neutrino-result-to-get-extra-checks.html
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Damn. 
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My physics Prof. actually addressed this in my lecture a few days after it was announced. He works at the Sudbury Neutrino Observatory, if that gives any more credibility.
Basically, what he said is that this result, even if they cannot determine any errors that may have accounted for the measurement, doesn't really mean anything until it can be reproduced independently. So, it's interesting, but it doesn't really mean anything right now.
That's how he put it, if I remember correctly. So, the thing to do is just wait, haha.
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On November 07 2011 02:58 Mr. Wiggles wrote:
My physics Prof. actually addressed this in my lecture a few days after it was announced. He works at the Sudbury Neutrino Observatory, if that gives any more credibility.
Basically, what he said is that this result, even if they cannot determine any errors that may have accounted for the measurement, doesn't really mean anything until it can be reproduced independently. So, it's interesting, but it doesn't really mean anything right now.
That's how he put it, if I remember correctly. So, the thing to do is just wait, haha.
Of course, you don't even have to be a physics prof. to make that statement, that just the way the scientific method functions. Something has to be reproduced numerous time before it can have any impact.
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On November 07 2011 02:58 Mr. Wiggles wrote:
My physics Prof. actually addressed this in my lecture a few days after it was announced. He works at the Sudbury Neutrino Observatory, if that gives any more credibility.
Basically, what he said is that this result, even if they cannot determine any errors that may have accounted for the measurement, doesn't really mean anything until it can be reproduced independently. So, it's interesting, but it doesn't really mean anything right now.
That's how he put it, if I remember correctly. So, the thing to do is just wait, haha.
Why do we need to wait? They found out last month it was an error and not true.. lol
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On November 07 2011 03:03 drsnuggles wrote:Show nested quote +On November 07 2011 02:58 Mr. Wiggles wrote:
My physics Prof. actually addressed this in my lecture a few days after it was announced. He works at the Sudbury Neutrino Observatory, if that gives any more credibility.
Basically, what he said is that this result, even if they cannot determine any errors that may have accounted for the measurement, doesn't really mean anything until it can be reproduced independently. So, it's interesting, but it doesn't really mean anything right now.
That's how he put it, if I remember correctly. So, the thing to do is just wait, haha. Of course, you don't even have to be a physics prof. to make that statement, that just the way the scientific method functions. Something has to be reproduced numerous time before it can have any impact.
Exactly, but it's in response to the over-reactions about this in the media. The first thing he did was show us about 10 headlines saying the speed of light has been broken, as a joke. I'm just stating it here, because I see some of the same. People just accepting it, or saying that if there's no errors found, then it's true. so I thought I'd post this. Sounds better coming from a physics Prof. than from Mr. Wiggles the random person though, haha.
On November 07 2011 03:09 `Zapdos wrote:Show nested quote +On November 07 2011 02:58 Mr. Wiggles wrote:
My physics Prof. actually addressed this in my lecture a few days after it was announced. He works at the Sudbury Neutrino Observatory, if that gives any more credibility.
Basically, what he said is that this result, even if they cannot determine any errors that may have accounted for the measurement, doesn't really mean anything until it can be reproduced independently. So, it's interesting, but it doesn't really mean anything right now.
That's how he put it, if I remember correctly. So, the thing to do is just wait, haha. Why do we need to wait? They found out last month it was an error and not true.. lol
I don't remember seeing that, link?
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Based on previous experiments that include the observation of a star reaching a state of supernova, neutrinos don't actually move faster than light, they just leave the source earlier than light does. When the star exploded, neutrinos arrived about 15 minutes before the photons did, which showed the star to be supernova. If the results of this test were accurate, the neutrinos would have arrived several years before the light did. I'm no physics major but this seems like enough to debunk this. Also there was said to be an issue with reference planes that applied to special relativity (which I won't pretend to understand) that could have lead to these results. All in all, I don't think these results are accurate, but hey, anything could happen! 
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They are rerruning the experiments right now so he's wrong.
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Hey, just because things might not defy our current laws of physics doesn't mean our physics is right.
It just means it's out best current answer based on the substantial data we have. I mean, we've only tapped the tip of the scientific iceberg so to speak! Right?
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On November 07 2011 03:18 Lucidx wrote:Based on previous experiments that include the observation of a star reaching a state of supernova, neutrinos don't actually move faster than light, they just leave the source earlier than light does. When the star exploded, neutrinos arrived about 15 minutes before the photons did, which showed the star to be supernova. If the results of this test were accurate, the neutrinos would have arrived several years before the light did. I'm no physics major but this seems like enough to debunk this. Also there was said to be an issue with reference planes that applied to special relativity (which I won't pretend to understand) that could have lead to these results. All in all, I don't think these results are accurate, but hey, anything could happen!
Dude, stop talking about things you don't know (i quoted this post, but i might have quoted many others).
You have no idea of how the measurements of Opera have been done, of what they expected, and you actually think that the whole Opera experiment is run by a bunch of idiots if you say something like I'm no physics major but this seems like enough to debunk this THEY KNEW THAT RESULT OBVIOUSLY! But as i said before, there was another result, in an experiment similar to Opera, but realized in USA (MINOS experiment), which showed results similar to Opera, but with very higher error (thus less certainty).
The thing that can explain the difference in the results of Opera and Tevatron from the supernova observation might be a dependence of neutrino velocity with their masses:
Average Opera neutrinos energy: 17 GeV
Average energy of Supernova SN1987A neutrinos: 7.5 to 39 MeV (1000 times less)
But now nobody knows, maybe there is an error in the measurements, maybe not, but please, think before saying that all the Physicists in an experiment are stupid enough to not find such obvious errors in their reasoning.
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1. The escapist is not a credible scientific source.
2. That's just a theory as to why the results were 'wrong'. In fact the CERN group claimed that they had taken this into account.
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Disclaimer: I'm a common idiot, took some physics but am not a physicist
Isn't something as simple as the relativity of the observers a very simple thing that should be accounted for? Especially from top notch scientists like these guys? This seems wrong, there's no way they made such a simple fuck up
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On November 07 2011 07:06 JamesJohansen wrote:
Disclaimer: I'm a common idiot, took some physics but am not a physicist
Isn't something as simple as the relativity of the observers a very simple thing that should be accounted for? Especially from top notch scientists like these guys? This seems wrong, there's no way they made such a simple fuck up
This was my line of thinking as well, 'If it's something I can come up with, that's not the reason'
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EPT
