CERN team claims measurement of neutrino speed >c

[miguel_barros]

miguel_barros: If you read the OPERA paper again, you will find the following quote:

"The baseline considered for the measurement of the neutrino velocity is then the sum of (730534.61 ± 0.20) m between the CNGS target focal point and the origin of the OPERA detector reference frame, and (743.391 ± 0.002) m between the BCT and the focal point, i.e. (731278.0 ± 0.2) m."

It appears that there is an additional distance of about 740 m between this BCT (Beam Current Transformer) that has to be added, except for the chord distance of 730 km or so between CERN and Gran Sasso. If the above sum (731287.0 +- 0.2) m is used when calculating the baseline in ns, the number at the top of p.49 in the ppt presentation you linked to is obtained.

Do check my answer above, you might have missed it, I didn't quote you and the GPS/time issue got in the way

 

[miguel_barros]

FURTHERMORE (in their own words)

"730085 m used as neutrino baseline from parent mesons average decay point"

even the 730534 m was too far, some decay took place further away from the SOURCE (target t40-s, source point for the geodesy study)decay point = source of the neutrinos, no neutrinos before that, just us Muons

average decay point = center signal to compare with OPERA

they had already shortened the distance from 730534 to 730085 because TT41 proton beam hitting the T40 target would not be enough to yeld the neutrinos, they had a decay tunnel for that but it was WITHIN the 730534 mwith C=299792458

the baseline should be: 0,002435301 s for central signal

they used 0,002439261

there is no physical room to place a magical 700 odd meters in before t40-s, not with neutrinos in it, not with timed time
check page 4

http://docs.google.com/viewer?a=v&q=cache:reYU9-LclQ0J:www.nithep.ac.za/3nr.file+%22%22The+ba%22The+baseline+considered+for+the+measurement+of+the+neutrino+velocity+is+then+the+sum+of+%22seline+considered+for+the+measurement+of+the+neutrino+velocity+is+then+the+sum+of&hl=en&pid=bl&srcid=ADGEESihVgRilHUi1p_6p-Vq-8MRohO9zeqAKk7fuHPFX77-do_W98xRI6vGPlxfFtjwPeqgYhliQZYaqT8WkC11vBBVjKIfLcmS3gufEFVH1fu1H_IKMDftMTUdTgExLN8DZO0pGewb&sig=AHIEtbSy1milgBxhewJi57N4-w3QfUtJPQ

and there is no distance available between TS40 and OPERA beyond 730534 m

Q.E.D.

EDIT where i mention TS40 it should read T40S

p.s. unless they thought the geodesy study was for THEIR detector and failed to notice (read) that 730 was for T40s, that would be an hubris worth of a greek tragedy

 

[FlexGunship]

I Google Maps'd it and found out that the distance they're using is actually the distance you'd have to drive if you only take major highways but avoid tolls.

So.

Yeah.

 

[DevilsAvocado]

Someone MUST CALL the OPREA team NOW!

 

[FlexGunship]

If a confirmation comes that neutrions travel faster than light, would the other particles that have been confirmed not to go faster than light be tested again to see if they go faster than light? Or is the FTL phenomena applicable only to neutrions?

Someone MUST CALL the OPREA team NOW!

OPREA must know about their neutrions!

 

[DevilsAvocado]

Yeah! :grumpy:

 

[Jorrie]

In Ramakrishna's paper, http://arxiv.org/ftp/arxiv/papers/1111/1111.1922.pdf , it very much nails the error in the Opera`s findings.

Given your question, how sure are you about your statement?

I think that (like van Elburg) Ramakrishna is barking up the wrong tree. He seems to be calculating a relativistic Sagnac effect in the frame of the orbiting common-view satellite. AFAIK, that frame of reference does not feature in any GPS calculations (apart from the initial offsetting of the satellite clock rates).

 

[miguel_barros]

I was preparing a private answer to someone who had a very constructive input, but I might as well leave it here as it seems more likely than the arch/chord.

Anyway, it's a simpler and prideful error that happened to mimic the arch-chord values

they used 730,534 km as distance from OPERA to THEIR CBT

the GEODESY study was from T40 S (target for proton beam, first muons and way upstream from their CBT)



no distance beyond 730,534 between T40s and OPERA

so no neutrinos before 0,002436801 s from OPERA (target 40) just protons

and they're using a 0,002439261 baseline because in a T40->CBT---->OPERA line they mis-read 730,534 as CBT---> OPERA and added the average T40->CBT where decay took place to an already too big CBT to Opera

best regards

Miguel Barros

p.s. if anyone CAN ask the CERN team if they took their detector or the target as the CERN point for the Geodesy value I think that would be worth doing...

 

[FlexGunship]

p.s. if anyone CAN ask the CERN team if they took their detector or the target as the CERN point for the Geodesy value I think that would be worth doing...

You have precisely the same abilities as the rest of us. Write it up, submit it for peer review, and get your paper published.

Also, your posts are getting progressively more difficult to read. As a courtesy to those of us reading, please concentrate on capitalization and punctuation; my eyes just glaze over after a sentence or two.

 

[miguel_barros]

I did not wish to bother.

Maybe one image can explain better than words.

Find 700 meters of error and I'll drop this right now.

Remember this is an Arch, not a Chord.

http://www.gpsvisualizer.com/map?lat1=46.246885&lon1=6.069517&lat2=42.44463405572&lon2=13.56281609083&convert_format=&gc_segments=&gc_altitude=&tickmark_interval=&show_wpt=3&add_elevation=&trk_colorize=&google_wpt_sym=circle&bearing_coords1=46.246885%2C+6.069517&distance=731.278&bearing=122.69&bearing_coords2=42.44463405572%2C+13.56281609083&format=google

 

[FlexGunship]

Find 700 meters of error and I'll drop this right now.

That's the thing... I don't think anyone is actually arguing your point, we just can't figure out why you keep pressing us. We're not CERN. This is www.physicsforums.com. We are a website. You should write your paper, get it peer-reviewed, get it published, get lavished with praised, and then get rich. Not a single one of us will stop you!

 

[The Lobster]

I have doubts about the validity of this experiment.

 

[Drakkith]

That's the thing... I don't think anyone is actually arguing your point, we just can't figure out why you keep pressing us. We're not CERN. This is www.physicsforums.com. We are a website. You should write your paper, get it peer-reviewed, get it published, get lavished with praised, and then get rich. Not a single one of us will stop you!

Does this really require a paper to be published and all that? I figured an e-mail or phone call or something to CERN would work. But I have no idea really.
Plus it seems like something really simple to be missed by so many people for so long.

 

[FlexGunship]

Plus it seems like something really simple to be missed by so many people for so long.

...

 

[StevieTNZ]

Perhaps email one of the authors?

 

[danR]

I mentioned earlier that the most rigorous test would be a foot-race between neutrino and light-pulses down an evacuated tube.

But if the phenomenon is real, that may not test for what someone cited earlier in this post: negative refractive index for neutrinos in (dense) matter:

http://arxiv.org/pdf/1109.5445v7

This elegant solution, they explain, would explain consistency between the CERN result(s), and SN1987a; neutrino velocities in vacuo do not exceed c, but they do exceed c in vacuo traversing matter.

In fact, we could generalize the notion; perhaps many particles suffer negative refractive effects, but the difference would be so tiny, that only the long distances that neutrinos can traverse through matter make a test practical.

 

[lalbatros]

I mentioned earlier that the most rigorous test would be a foot-race between neutrino and light-pulses down an evacuated tube.

But if the phenomenon is real, that may not test for what someone cited earlier in this post: negative refractive index for neutrinos in (dense) matter:

http://arxiv.org/pdf/1109.5445v7

This elegant solution, they explain, would explain consistency between the CERN result(s), and SN1987a; neutrino velocities in vacuo do not exceed c, but they do exceed c in vacuo traversing matter.

In fact, we could generalize the notion; perhaps many particles suffer negative refractive effects, but the difference would be so tiny, that only the long distances that neutrinos can traverse through matter make a test practical.

This would only be a reformulation of the problem.
Such an interaction between neutrino and rocks would defeat causality and would allow FTL communication. It would also imply some collective FTL process in the rocks which would also be contradictory with anything we know. In addition, neutrinos do not interact mcuh with matter, and therefore the "index of refraction" should be quite close to 1.

 

[danR]

This would only be a reformulation of the problem.
Such an interaction between neutrino and rocks would defeat causality and would allow FTL communication. It would also imply some collective FTL process in the rocks which would also be contradictory with anything we know. In addition, neutrinos do not interact mcuh with matter, and therefore the "index of refraction" should be quite close to 1.

I think you have missed key elements of the paper:

In this experiment, neutrinos seem to behave, during the 735 km travel, either as tachyons or as they had a pseudo-tachyonic behavior when transversing a material, like photons in meta-materials [9, 10] with negative refractive index or less than unity, that allows an apparent superluminal propagation without violating causality.​

[emph added]

and with reference to phase velocity:

As vg > vp, the medium would cause the speed of only certain Fourier components of neutrino wavefunction in it to be larger than the speed of light in vacuum for a band of neutrino oscillation frequencies obeying the Majorana condition p ≥ kc, but seems to be forbidden by CG effect for a standard neutrino.​

Mere phase-velocity would not allow FTL communication, and the implications of the paper is that Einstein was, again, correct: nothing communicative can travel faster than c in vacuo.

 

[miguel_barros]

Last reflection that I had as I slowly find that I might have erred on the distance error...

could the anomaly be due to an additional laggard decay on the hadron stopper?

18 meters (3 graphite 15 iron) =60 ns

It wouldn't be as nice as a vacuum but those that survived, survived.

Specially with the additional extraction made by the first 3 meters of graphite of the Hadron stopper

It might be visible on the neutrino detection form:

- two normal functions instead of one,
- even, one might dream, neutrino interference patterns

And the effect could be different on different sized beams.

- larger sized beams could give bigger signals

It might explain the difference between higher and lower energy neutrinos anomaly

- kaons still decaying in the stopper
- freshly made kaons, graphite stopper, decaying fast in the stopper and beyond

As the TOF is compared on a form fitted PDF, with an additional 60ns of true extraction, assuming that the last to arrive were the last protons, we'd assume the first had arrived 60 seconds earlier.

Any comments?

Best regards

 

[Centri-Fagin]

'Faster than light neutrinos' accelerate?

Does anybody know if the neutrinos sent from CERN to Gran Sasso have their speed measured beofre the leave the CERN facility?
CERN shoot their hadrons around at 99.9% the speed of light?
If the neutrinos are also 'built up' to this speed then for the readings that they are getting at Gran Sasso (faster than speed of light), the neutrinos would not only travel faster than light but also be accelerating without additional energy?

 

[miguel_barros]

Does anybody know if the neutrinos sent from CERN to Gran Sasso have their speed measured beofre the leave the CERN facility?
CERN shoot their hadrons around at 99.9% the speed of light?
If the neutrinos are also 'built up' to this speed then for the readings that they are getting at Gran Sasso (faster than speed of light), the neutrinos would not only travel faster than light but also be accelerating without additional energy?

That's not how it works

They have 2 syncronized clocks and a light speed baseline for the TOF

then they use the Proton Waveform and the timestamp to establish a maximum likehood function that should match the neutrino function at arrival

They take the arrival and match it and test it against the speed of light baseline.

As I mentioned above this could lead to the 60 ns anomaly being the fact that there is no magic stoper and the aditional 18 meters of the "HADRON STOPPER" being in fact a new (if less than perfect) target for the production of kaons and their decay to muon neutrinos.

 

[Imax]

A possible experiment to confirm OPERA results:

What could happen, hypothetically, if the OPERA results were valid, and you could drop a neutrino emitter down a black hole?

 

[lalbatros]

I think you have missed key elements of the paper:

In this experiment, neutrinos seem to behave, during the 735 km travel, either as tachyons or as they had a pseudo-tachyonic behavior when transversing a material, like photons in meta-materials [9, 10] with negative refractive index or less than unity, that allows an apparent superluminal propagation without violating causality.​

[emph added]

and with reference to phase velocity:

As vg > vp, the medium would cause the speed of only certain Fourier components of neutrino wavefunction in it to be larger than the speed of light in vacuum for a band of neutrino oscillation frequencies obeying the Majorana condition p ≥ kc, but seems to be forbidden by CG effect for a standard neutrino.​

Mere phase-velocity would not allow FTL communication, and the implications of the paper is that Einstein was, again, correct: nothing communicative can travel faster than c in vacuo.

I understand that the OPERA experiment measured particles velocities, which are group velocities.

A refractive index represents an interaction between a wave or a particle and matter, rocks here.

For example, the refractive index of homogeneous classical plasmas can be studied in full detail from the laws of classical mechanics and electrodynamics. The refractive index of a plasma is caused by the interaction and response of the plasma (the matter) to the wave. Usually (necessarily), this index of refraction changes with the frequency (energy), and causality then also implies an absorption of the wave.
A particle point of view or a quantum dynamics approach (necessary for plasmas below the fermi level) does not change the global picture.

In summary: a refractive index different from 1, should imply an interaction with matter as well as an absorption.

Knowing the extremely weak interaction of neutrinos with matter, I can't see how this could lead to a refractive index, even 10^-5 close to 1.

If the neutrinos have a FTL light, this can in no way be "explained" by a "refractive index".
The presence of rocks should therefore play no role in the FTL velocity of neutrino, and the same result should be expected for neutrino propagating through vacuum.
Therefore this "refractive index" is even not related to the "rocks", which is a strange syntax for a refractive index.
You could of course call v/c a "refractive index", but this would explain nothing.
I could as well say that I am driving my car at a very low refractive index.

 

[miguel_barros]

Just a small correction on my last comment

The distortion caused by the second target (hadron stopper) might be much bigger on the muon (initial image) sensors than on the neutrinos detected at OPERA.

I would really like to see the result of a run without the primary target T40-s, just the muon image and detected neutrinos from the Hadron Stopper.

Maybe then they would see that the difference between the 1048 ns blind calibration and their individual effects of around 1000 ns is the 60 ns hadron stopper distortion.

 

[lalbatros]

That's not how it works

They have 2 syncronized clocks and a light speed baseline for the TOF

then they use the Proton Waveform and the timestamp to establish a maximum likehood function that should match the neutrino function at arrival

They take the arrival and match it and test it against the speed of light baseline.

As I mentioned above this could lead to the 60 ns anomaly being the fact that there is no magic stoper and the aditional 18 meters of the "HADRON STOPPER" being in fact a new (if less than perfect) target for the production of kaons and their decay to muon neutrinos.

Miguel,

The only delay that matters is the time elapsed between a signal on the Beam Current Transformer (BCT) and the OPERA detector in Gran Sasso.

It does not matter that the conversion from protons to kaons and from kaons to neutrinos occurs further downstream. This is because the protons and kaons have high energies and travel extremely close to the speed of light.

In particular, additional kaons that would be produced in the Hadron Stopper would in no way modify the result. Those neutrinos originating from the Hadron Stopper should come exactly at the same time in Gran Sasso than other neutrinos originating from the main target.

This is precisely the magic of the constancy of the speed of light.
But it might be challenged now.

Michel

 

[miguel_barros]

I assume you haven't read my last correction.

Most likely those "Hadron Stop Born" muons don't have time to decay, but there are plenty and they do show up on the muon monitors.

Furthermore not all protons have the same energy and so the fraction of speed of light they travel is proportional to their energy.

Fore-runners and laggards will skew the CBT timestamped muon "origin" picture, specialy if one assumes that the only origin of muons is at the Target (1 km before the Hadron Stop)

How does it affect the result? Maybe that's the reason they had to do a "blind calibartion" adding 1048 ns to the baseline when the explained items amounted to (in their own words) "~1000 (ns)".

Maybe it skews the medium point of decay.

It will most likely distort the picture being fitted to the "arrival" signal.

If any, or all, of these effects take place the 60 ns difference is trivial.

BTW, as a simple rule I would not consider publishing anything stating that a "blind calibration" had been used because the internal delays added up to ~1.000 and I hadn't found out why I needed 1048.

Specialy when it finishes with a 60 ns revolutionary conclusion.

 

[BobCastleman]

This will seem hopelessly simplistic, but aren't they saying that the neutrinos arrived sooner than light if the light had traveled the same path? How can you say that a photon leaving the neutrino source at the same moment, traveling the same path, would arrive later (or sooner) than the neutrinos? Aren't they comparing an ACTUAL measurement with a theoretical value? To say that it actually traveled faster than light would one not have to measure both the photons and the neutrinos under the same conditions?

 

[Passionflower]

This will seem hopelessly simplistic, but aren't they saying that the neutrinos arrived sooner than light if the light had traveled the same path? How can you say that a photon leaving the neutrino source at the same moment, traveling the same path, would arrive later (or sooner) than the neutrinos? Aren't they comparing an ACTUAL measurement with a theoretical value? To say that it actually traveled faster than light would one not have to measure both the photons and the neutrinos under the same conditions?

The thing is, they claim to know the exact coordinate distance and time the neutrinos traveled, thus if you know the distance and the time you know the velocity. It is claimed this velocity is faster than light.

Thus the questions are:
- Is the coordinate distance correct?
- Is the elapsed coordinate time correct?

 

[BobCastleman]

The thing is, they claim to know the exact coordinate distance and time the neutrinos traveled, thus if you know the distance and the time you know the velocity. It is claimed this velocity is faster than light.

Thus the questions are:
- Is the coordinate distance correct?
- Is the elapsed coordinate time correct?

But the experiment boils down to neutrinos traveled from point A to point B in some time X. In theory, light would travel from the SAME point A to the SAME point B in some time X-n. But they can't measure light moving from the same A to B, they can only calculate what it should be, no? Without the actual measurement of light, then they can only say that the neutrinos were faster than the theoretical speed of light along THAT path. But unless they shoot a beam of photons from that A to that B, and actually measure it, their claim of super luminal speed is "on paper", as it were.

Haven't other observations of neutrinos confirmed sub-luminal speeds? Isn't it more Occam's Razorish to assume that the conditions of the experiment are the issue rather than overturning a fundamental piece of physics?

I do understand this is a very intriguing observation. Quite disruptive, one might say. It will be fascinating to watch it lay out.

 

[Aether]

But they can't measure light moving from the same A to B, they can only calculate what it should be, no?

It is not possible to actually measure the one-way speed of light in any way that is consistent with Special Relativity. Neither is it possible to "calculate what it should be". What actually happens is that the one-way speed of light is assumed to be c, and a coordinate system (an inertial frame) is constructed wherein this assumption automatically holds true. The two-way speed of light (isotropy) is what can actually be measured.

Without the actual measurement of light, then they can only say that the neutrinos were faster than the theoretical speed of light along THAT path. But unless they shoot a beam of photons from that A to that B, and actually measure it, their claim of super luminal speed is "on paper", as it were.

That's right. In their paper, the OPERA team claims:

An early arrival time of CNGS muon neutrinos with respect to the one computed assuming the speed of light in vacuum of (60.7 ± 6.9 (stat.) ± 7.4 (sys.)) ns was measured.

 

[BobCastleman]

It is not possible to actually measure the one-way speed of light in any way that is consistent with Special Relativity. Neither is it possible to "calculate what it should be". What actually happens is that the one-way speed of light is assumed to be c, and a coordinate system (an inertial frame) is constructed wherein this assumption automatically holds true. The two-way speed of light (isotropy) is what can actually be measured.

If you cannot measure the speed of light one-way, then how can you accurately transmit the information to the other end that signals the start time? If point A initiates an event, then point B needs to know the time of initiation. Basically, the neutrinos arrive before the signal of the start time, since the signal is being bounced off a satellite, or sent over a fiber optic cable or some such thing and is not traveling at c.

It must be a tricky calculation, seeing as both ends of the experiment are accelerated reference frames via the rotation of the earth. Wouldn't they they be under different accelerations based on their latitude and altitude? Wouldn't the entire path of the transmitted start signal also be subject to acceleration issues in the calculations? I assume they had to use numerical methods to do all those calculations. It would be ironic to find that the intrinsic errors in computerized floating point arithmetic caused the anomaly.

 

[Angry Citizen]

Without the actual measurement of light, then they can only say that the neutrinos were faster than the theoretical speed of light along THAT path. But unless they shoot a beam of photons from that A to that B, and actually measure it, their claim of super luminal speed is "on paper", as it were.

I may be mistaken, but I believe this is a non-issue. The neutrinos violated c, not the speed of light. That should not be happening under the conditions of SR.

 

[BobCastleman]

I may be mistaken, but I believe this is a non-issue. The neutrinos violated c, not the speed of light. That should not be happening under the conditions of SR.

Yes, I understand that now.

 

[Passionflower]

Yes, I understand that now.

Then you understand more than I as in my understanding c is the speed of light in vacuum.

 

[ChrisPhy]

Given the small (to me it's small) amount measured beyond c, and where speed is just distance / time...
1) How is it they are so certain to the exact distance involved in this experiment ?
2) How did they rule out possibility that with the slight increase in energy density along the path of the experiment that the length did not momentarily compress by a fraction of a mm. ?