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Faster-Than-Light Neutrino Puzzle Claimed Solved by Special Relativity

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Jim__ Donating Member (1000+ posts) Send PM | Profile | Ignore Fri Oct-14-11 09:45 AM
Original message
Faster-Than-Light Neutrino Puzzle Claimed Solved by Special Relativity
Dutch scientist claims to have found the error that accounts almost exactly for the measured difference between the allowable time (travelling at the speed of light) and the measured time. Presumably he knows that the OPERA team did not take this into account.






...

So from the point of view of a clock on board a GPS satellite, the positions of the neutrino source and detector are changing. "From the perspective of the clock, the detector is moving towards the source and consequently the distance travelled by the particles as observed from the clock is shorter," says van Elburg.

By this he means shorter than the distance measured in the reference frame on the ground.

The OPERA team overlooks this because it thinks of the clocks as on the ground not in orbit.

How big is this effect? Van Elburg calculates that it should cause the neutrinos to arrive 32 nanoseconds early. But this must be doubled because the same error occurs at each end of the experiment. So the total correction is 64 nanoseconds, almost exactly what the OPERA team observes.

more ...

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MineralMan Donating Member (1000+ posts) Send PM | Profile | Ignore Fri Oct-14-11 09:51 AM
Response to Original message
1. Well, that argument makes sense to me as an amateur follower
of such things. If it proves out, as I expect it will, then there's been a re-affirmation of special relativity, not a repudiation.
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Jim__ Donating Member (1000+ posts) Send PM | Profile | Ignore Fri Oct-14-11 09:57 AM
Response to Reply #1
2. It seems strange that the OPERA team would have overlooked that.
I guess these computations are so complex that even the experts can miss things.
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MineralMan Donating Member (1000+ posts) Send PM | Profile | Ignore Fri Oct-14-11 10:03 AM
Response to Reply #2
3. I really don't know. I can follow this stuff on a conceptual basis,
but not at an academic level. I've been reading stuff on high-energy physics for a very long time, but don't have the math capabilities to follow the details. I'm pretty much an abstract reader for scientific papers. The rest of the papers are pretty impenetrable for me.
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caraher Donating Member (1000+ posts) Send PM | Profile | Ignore Fri Oct-14-11 05:36 PM
Response to Reply #3
7. Did you look at this one?
There's not much math, actually. It's an astonishingly simply possible explanation.
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bananas Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Oct-15-11 04:08 PM
Response to Reply #7
9. I think it's been accounted for
Edited on Sat Oct-15-11 04:29 PM by bananas
I took a quick look at the usno pdf mentioned here and it seems to cover this subject pretty thoroughly:
http://www.kurzweilai.net/faster-than-light-neutrino-pu...

Faster-than-light neutrino puzzle claimed solved by special relativity
October 14, 2011 by Editor

The relativistic motion of clocks on board GPS satellites exactly accounts for the superluminal effect in the OPERA experiment, says physicist Ronald van Elburg at the University of Groningen in the Netherlands, The Physics arXiv Blog reports.

<snip to comments>



October 14, 2011
by gvseostud

My fear is that this paper will only add to the confusion regarding GPS time. Any complete treatment of GPS time should discuss how a ground receiver is using time, in accordance with ICD-GPS-200:

http://www.navcen.uscg.gov/pubs/gps/icd200/ICD200Cw1234...

This has been debated already in literature here:

http://tycho.usno.navy.mil/ptti/1996/Vol%2028_16.pdf

The conclusion was that relativistic corrections were being accounted for by OCS Kalman filtering to within 2.5mm, for time of flight corrections to within 8 pS.

I am not saying there are not systematic errors in the propagation of GPS time, but I am saying that van Elburgs paper is not a good treatment of them.

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October 14, 2011
by gvseostud

Note especially this quote from the second linked reference:

this error would be incurred only if the station clocks were independent of the GPS satellite clocks, each MS keeping its own time. Thats not the way the OCS works. Station time is estimated in the Kalman filter together with the SV clocks, and each MS clock is effectively being updated continuously by the satellites. The station clock is used only to bridge the gap in time between measurements; but since several satellites are always in view, these measurements are virtually instantaneous, except for the different signal propagation times from different satellites. These times are about 0.1 sec, and, multiplying by 7, once more we derive an error of about 2.5 millimeters.

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Schema Thing Donating Member (1000+ posts) Send PM | Profile | Ignore Fri Oct-14-11 10:14 AM
Response to Reply #2
4. yes and no. It's easy to overlook the simplest of things when you are

preoccupied with other, much more intense concepts/mechanics.
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bananas Donating Member (1000+ posts) Send PM | Profile | Ignore Fri Oct-14-11 10:31 AM
Response to Original message
5. They should look for correlation between satellite position and observed time-of-flight
The paper says: "In addition full analysis should be able to predict the correlation between the GPS satellite position(s) and the observed time-of-flight."
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bananas Donating Member (1000+ posts) Send PM | Profile | Ignore Fri Oct-14-11 11:57 AM
Response to Reply #5
6. Hmm...
http://www.science20.com/quantum_diaries_survivor/tambu...

Tamburini: Neutrinos Are Majorana Particles, Relativity Is OK
By Tommaso Dorigo | October 10th 2011 07:25 AM

<snip>

What I find interesting is that Tamburini and Laveder do not stop at discussing the theoretical interpretation of the alleged superluminal motion, but put their hypothesis to the test by comparing known measurements of neutrino velocity on a graph, where the imaginary mass is computed from the momentum of neutrinos and the distance traveled in a dense medium. The data show a very linear behaviour, which may constitute an explanation of the Opera effect:




Dataset E(GeV) T/T0 m(GeV) m
OPERA high 42.9 2.76 10−5 0.317 0.093
OPERA 17GeV 17 2.48 10−5 0.119 0.028
OPERA low 13.9 2.18 10−5 0.092 0.035
MINOS 3 5.10 10−5 0.030 0.017
SN1987a 4 10−2 2 10−2 0.019 0.008


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Eddie Haskell Donating Member (817 posts) Send PM | Profile | Ignore Fri Oct-14-11 05:58 PM
Response to Original message
8. What did I tell you?
Edited on Fri Oct-14-11 06:09 PM by Eddie Haskell
:toast: to me.
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