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In general, either neutrinos will be indeed found to be faster than light, or they will find a measurement error. So the paper will be either a great discovery or a great shame. It's a lottery for these people and their will to sign it is proportional to their belief how much of either will it be.

Shouldn't a paper be just a report of an experiment. Factors such as greatness or shame are subversive and discredit the neutrality of science.

Maybe I overlooked it in the other comments and has it already been posted.

if not, here's a fun documentary on the subject.


FASTER THAN THE SPEED OF LIGHT Marcus du Sautoy (BBC 2 2011)

part 1 of 4 http://www.youtube.com/watch?v=EedEA2MHRRM

part 2 of 4 http://www.youtube.com/wa...Bf3Ic&feature=related

part 3 of 4 http://www.youtube.com/wa...16th4&feature=related

part 4 of 4 http://www.youtube.com/wa...fy6OE&feature=related

Kasuha wrote:In general, either neutrinos will be indeed found to be faster than light, or they will find a measurement error. So the paper will be either a great discovery or a great shame. It's a lottery for these people and their will to sign it is proportional to their belief how much of either will it be.

One point to consider is that this issue *isn't* primarily what the OPERA experiment was set up to do. They are doing lots of stuff in terms of examing the properties of neutrinos, this measurement was a complete surprise to them and wasn't really what they were looking for. So hence if it turns out to be wrong it won't be a huge disaster for them, certainly it won't undermine the whole point of the experiment.

Post moved. Apologies.

DCWhitworth wrote:One point to consider is that this issue *isn't* primarily what the OPERA experiment was set up to do. They are doing lots of stuff in terms of examing the properties of neutrinos, this measurement was a complete surprise to them and wasn't really what they were looking for. So hence if it turns out to be wrong it won't be a huge disaster for them, certainly it won't undermine the whole point of the experiment.

You're right, OPERA team has clearly done all they could to narrow down possible errors. They did very good job on it and they deserve to be proud of it. Now it might be the time to let them return to their primary task (neutrino oscillations) and perhaps prepare another experiment which is primarily aimed at precise measurements of neutrino speeds.
Regarding their paper, though, even though their statement is "we measured this delay on this distance", almost everyone else in the world interprets it as "we claim neutrinos are faster than light" and to be honest, if it was me to sign under that paper, I'd probably hesitate too.

LMDyer wrote:On reading Giulia’s thesis, we see there are 41 pages on Timing and Corrections.
What ? 41 pages !
This is telling us something.

Of course it is - it's all about measurements of time and distance and the point of the paper is to let others try to find if they forgot something.

LMDyer wrote:Well, Watson; simple science is elegant science and this is clearly not simple.

This is actually science at its simplest. Time and distance, that's all it is about. It doesn't even involve any complicated math.

LMDyer wrote:Synchronise another cesium clock to the CERN GPS 1nsec time.
Take the cesium clock down to the second muon detector, inject false ‘muon’ pulses into the detector, triggered from the cesium clock.
Acquire time-stamps for those triggers.
Time-stamp the muon detector output. Use another set of the same time-stamping hardware/software and the same time-data source as the proton-pulse time-stamper, not from the new cesium clock.

Is a “Fast Waveform Digitiser” FWD still being used even for the 3 nsec proton pulses ?
If so, use another FWD from a different company for the above muon-detector readout.
Do the various time-stamps correspond ?
There are other simple permutations to the above experiment.

They already did all of that. Not exactly the way you describe but in a way which I consider equal to it.

This has been up in the news the last few days:

Study rejects "faster than light" particle finding

In a paper posted Saturday on the same website as the OPERA results, arxiv.org/abs/1110.3763v2, the ICARUS team says their findings "refute a superluminal (faster than light) interpretation of the OPERA result."

They argue, on the basis of recently published studies by two top U.S. physicists, that the neutrinos pumped down from CERN, near Geneva, should have lost most of their energy if they had travelled at even a tiny fraction faster than light.

But in fact, the ICARUS scientists say, the neutrino beam as tested in their equipment registered an energy spectrum fully corresponding with what it should be for particles traveling at the speed of light and no more.

Source: http://www.reuters.com/article/2011/11/ ... ZX20111120

I've seen this quite a long ago so I'm surprised it's placed as something new (maybe they were refining the paper too?) but I don't think it can be used as a proof for non-superluminal neutrinos. The reasoning goes:

We have theory T which explains superluminal neutrinos but according to T such neutrinos must produce electron-positron pairs.

If such pairs were detected, then it would be indication that T may be true (or close to truth) and neutrinos are indeed superluminal. But it doesn't go both ways. Absence of such pairs means that neutrinos cannot be superluminal only if T is true. And as long as there is no proof that T is true and there is potentially infinite number of theories that may explain superluminal neutrinos, the conclusion is obvious - it does not prove anything.

I don't believe neutrinos are superluminal - the supernova coincidence is way too heavy for that idea. The furthest I am willing to go if I assume that OPERA got it really right is that there is a constant shift of some 60 ns rather than speed difference. I even have an explanation for this shift but it's too crackpottish to be posted here.

LHC could shed light on superluminal neutrinos http://physicsworld.com/cws/article/news/47886

Hmm

And More good stuff from Matt Strassler.
Why Icarus doesnt refute Opera
http://profmattstrassler.com/2011/11/21 ... ute-opera/

And

Opera comparing the two versions.
http://profmattstrassler.com/articles-a ... -versions/
With lots of illustrations and good explanations of Opera' two Neutrino time of flight experiment results.

We have to wait for Minos to update their timing apparatus, shoot some Neutrinos and get some hopefully illuminating data.
Eventually

" The MINOS collaboration is currently investigating available methods to improve its neutrino time-of-flight measurement using its existing data, as well as improvements for future data-taking, both utilizing features that newer GPS and time-keeping hardware can offer. "
http://www-numi.fnal.gov/PublicInfo/forscientists.html

And live Tweets from King's College
http://www.kcl.ac.uk/nms/depts/physics/ ... Event.aspx

Dr Ben Still https://twitter.com/#!/benstill/status/ ... 3645253633
18-33 ns uncertainty could be possible from re-analysis of current MINOS data of 11-18 after hardware upgrade and 12 months data from 2012..

Dr Ben Still https://twitter.com/#!/benstill/status/ ... 1248610304
MINOS aim a systematic (experimental) uncertainty of 5-7ns for data taking 2013 and beyond, around the OPERA accuracy - so about three years

Dr Ben Still https://twitter.com/#!/benstill/status/ ... 4688871426
As with other experiments in the field the improvements in MINOS systematic uncertainty will come from GPS timing improvement.


So three years till refutation or confirmation of Opera's results.

Hi, I'm new here. I'm not a scientist, I work with wood.

Yet I would like to suggest a simple theory

If a human travels from A to B on the suface of the earth, ( slower than light) in a straight line, perhaps he is a sailor in a boat on the sea, than this line would not be really straight, because the earth's surface is curved.
If a neutrino travels from A to B it goes straight through the earth. They don't care that the space inside the earth is full of rock and stuff.
If a neutrino comes from a distant star, it travels through empty space at precisely the speed of light.
On earth there is gravity. Nowadays gravity is explained as space that is curved. This impicates that there is yet another dimension outside space that we don't know much about, exept that space (or spacetime to be precise) is curved in it by gravity.
Now our neutrino's don't care much about gravity either. So if they take like yet another shortcut, that might explain for the sixty nanoseconds they arrived to early.
So here is my question: can you scientists, knowing how much gravity we have on earth, calculate how much space is curved?
The line straight through earth from CERN to the place were they were detected is still not really straight, only in space it looks like a straight line. In hyperspace it follows the curve of space itself.
Now if it is possible to calculate how much shorter a real straight line would be compared to a line following the curve of space, than we also would know if at the speed of light it indeed makes sixty nanoseconds difference.

Space distortion by gravity is actually making the path longer. And in case of Earth's gravity the difference is unmeasurably small.

I think if the results of Cern stand up to further investigation what may be going on is another form of chronology protection. Basically, nature in high energy events could select a simular to normal, but raised value of C whereby chronology protection or invariance is protected. In that altered micro-bubble vacuum while C would be higher the particles themselves would still travel at the same percentage of that new C they would have in the old C. Thus, no energy increase, no tachyon events, etc.

More developments.

http://www.symmetrymagazine.org/breakin ... imekeeper/

"When Demetrios Matsakis, the head of the U.S. Naval Observatory department that deals with measuring time, received an email from a Fermilab physicist in late September, he had immediate suspicions. The physicist asked if a two-way satellite transfer, one of the Naval Observatory’s specialties, would work in a particular timing measurement.
“This is about neutrinos, isn’t it?” Matsakis wrote back. Yes, it was."