CERN team claims measurement of neutrino speed >c


by turbo
Tags: anisotropy, cern, ftl, gps, new math books
Orion1
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#757
Mar17-12, 06:49 AM
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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.

"The result is compatible with the simultaneous arrival of all events with equal speed, the one of light." - ref. 2

Reference:
A search for the analogue to Cherenkov radiation by high energy neutrinos at superluminal speeds in ICARUS - ICARUS
Measurement of the neutrino velocity with the ICARUS detector at the CNGS beam. - ICARUS
Vanadium 50
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#758
Mar17-12, 07:54 AM
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It looks like it's that time again:

Before posting in this thread, we'd like to ask readers to read three things:

We think this will make the discussion go smoother.

V50, for the Mentors.
exponent137
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#759
Mar18-12, 03:27 AM
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Let us assume that we measure speed and energy of neutrinos in the opposite direction that pions and kaons fly toward the target.
Is it so possible to reduce some velocities of neutrinos so much, that difference v-c would be measured?

p.s. According to Fig 1 in the mentioned article, pions and kaons fly toward the target.
lalbatros
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#760
Mar18-12, 05:08 AM
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A few months were enough to cast serious doubts on the OPERA results.
The doubts originated from within the team itself.
The famous OPERA paper was of no use in this process.
One may then seriously question why this paper was published at all.
Was it too difficult to wait one more year?
After all, the main result will be that neutrinos propagates at the speed of light.
The headlines about FTL neutrinos will remain as a big mistake.
gvk
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#761
Mar18-12, 09:10 AM
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"One may then seriously question why this paper was published at all. Was it too difficult to wait one more year?"

Time is not a matter. It was the result of measurements during past 5 yrs, and as any team they should publish results regularly. The unusual thing they did not check equipments during this period of time. Any strange result should immediately draw their efforts to find faulty equipments. Their desire to make discovery was stronger.
lalbatros
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#762
Mar18-12, 09:28 AM
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As you said, gvk, they should have checked their equipment.
This is a question of taking what it needs to do these checks: mainly time.
There cannot be good arguments for deliberately publishing a wrong result.

It is really striking for me how much the OPERA team stressed the statistical errors of their measurement, when at the same time they completely neglected the systematic errors.
It has often been said that such a big team of experts could not make beginners mistakes.
Yet, this is exactly what they did:
- over-confidence in their equipment
- neglect of systematic errors
- blind confidence in an irrelevant statistical analysis
There will probably be two things to be remembered from this story:
- neutrinos propagates at the speed of light
- do not trust anything, specially your equipment
OnlyMe
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#763
Mar18-12, 02:33 PM
P: 52
Quote Quote by Orion1 View Post

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.

"The result is compatible with the simultaneous arrival of all events with equal speed, the one of light." - ref. 2

Reference:
A search for the analogue to Cherenkov radiation by high energy neutrinos at superluminal speeds in ICARUS - ICARUS
Measurement of the neutrino velocity with the ICARUS detector at the CNGS beam. - ICARUS
The issue involved here represents "null" results when looking for a proposed analogue Cherenkov radiation associated with FTL neutrinos. What I mean here is though the original paper by Glashow and Cohen has merit, it is a theoretical paper, with no confirmation. Until the theorized analogue Chenkov radiation has been experimentally confirmed any experiment that fails to detect it, represents a failure to detect it, not proof that it exists, does not exist or that neutrinos cannot exceed c.

The problem is, that to experimentally confirm the analogue radiation the FTL neutrinos must first be confirmed. FTL neutrinos remain questionable and likely will not be put to rest until later this year when additional experiments have been conducted at both CERN/OPERA/ICAUS(?) and MINOS. Even then a full examination may require more than a single season, unless the current systemic issue can be proven the origin of the original data and conclusions.
Plebeian
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#764
Apr10-12, 12:28 PM
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So the head of the Opera team resigned and now they are saying that Neutrinos travel at the speed of light. Don't Neutrinos have mass? If so how can they travel at the speed of light?

http://www.bbc.co.uk/news/science-environment-17560379

Sandro Centro, co-spokesman for the Icarus collaboration, said that he was not surprised by the result.

"In fact I was a little sceptical since the beginning," he told BBC News at the time.

"Now we are 100% sure that the speed of light is the speed of neutrinos."
PAllen
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#765
Apr10-12, 01:10 PM
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Quote Quote by Plebeian View Post
So the head of the Opera team resigned and now they are saying that Neutrinos travel at the speed of light. Don't Neutrinos have mass? If so how can they travel at the speed of light?

http://www.bbc.co.uk/news/science-environment-17560379

Sandro Centro, co-spokesman for the Icarus collaboration, said that he was not surprised by the result.

"In fact I was a little sceptical since the beginning," he told BBC News at the time.

"Now we are 100% sure that the speed of light is the speed of neutrinos."
Please read at least some prior posts. This has been explained at least a dozen times in this thread. See, most recently, #751.
Creator
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#766
Apr10-12, 01:38 PM
P: 534
Quote Quote by lalbatros View Post
There will probably be two things to be remembered from this story:
- neutrinos propagates at the speed of light
- do not trust anything, specially your equipment

Yea; and one more thing :
-- erroneous news always propogates faster than reality. :)

....
alexg
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#767
Apr10-12, 08:37 PM
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Nothing in the Universe moves faster than rumor.
Zarqon
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#768
Apr11-12, 03:38 AM
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Quote Quote by alexg View Post
Nothing in the Universe moves faster than rumor.
which is not breaking FTL because rumors on average contain no real information ;)
muhla
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#769
May31-12, 08:01 AM
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Hello falks! Can anybody inform me about last Opera experiment results? More specifically:
-How much energy was spent to run the neutrinos at C? Because according to relativity it needs infinite energy.And two relative questions:1.Can a particle be entirely converted to energy? 2.Does energy always have a carrier particle? Thanks a lot.
Whovian
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#770
May31-12, 10:34 AM
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Quote Quote by muhla View Post
-How much energy was spent to run the neutrinos at C?
What do you mean? They can't go at c. Perhaps you mean extremely close to c? In which case one would use the relativistic formula for kinetic energy.

Can a particle be entirely converted to energy?
If it annihilates with its antiparticle, yes.

Does energy always have a carrier particle?
Do you mean that you're wondering if all energy manifests itself as the mass of a particle? I don't think so, due to Special Relativity, but I'm not exactly a reliable source for this sort of stuff, and the Higgs (if it turns out to be an existent particle) would complicate things.
Histspec
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#771
Jun8-12, 05:21 AM
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The Gran Sasso experiments OPERA, ICARUS, LVD, BOREXINO presented preliminary results of the new neutrino speed measurements in May 2012- they are consistent with the speed of light within margin or errors:

http://francisthemulenews.wordpress....tados-de-2012/ (in Spanish)

Borexino: δt = 2.7 1.2 (stat) 3(sys) ns
ICARUS: δt = 5.1 1.1(stat) 5.5(sys) ns
LVD: δt = 2.9 0.6(stat) 3(sys) ns
OPERA: δt = 1.6 1.1(stat) [+ 6.1, -3.7](sys) ns

OPERA has also revised their 2011 results and will resubmit it to the "Journal of High Energy Physics":
δt = (6.5 7.4 (stat.)+9.2 (sys.)) ns

Also MINOS from Fermilab corrected their former results
δt = −11.4 11.2 (stat) 29 (syst) ns (68% C.L)

So Einstein is still laughing...
ZapperZ
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#772
Jun8-12, 05:57 AM
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The press announcement from CERN on this result can be found here:

http://press.web.cern.ch/press/Press.../PR19.11E.html

Zz.
sshai45
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#773
Jun8-12, 01:44 PM
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Yet more awards to put into the impressive trophy collection Einstein's theories hold...
StevieTNZ
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#774
Jun10-12, 01:38 PM
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The latest on Physorg:
http://phys.org/news/2012-06-einstein-neutrino.html

Scientists on Friday said that an experiment which challenged Einstein's theory on the speed of light had been flawed and that sub-atomic particles -- like everything else -- are indeed bound by the universe's speed limit.


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