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Author Topic: Faster than light neutrinos?  (Read 13209 times)

Offline JP

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Offline Geezer

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Faster than light neutrinos?
« Reply #26 on: 23/09/2011 23:41:43 »
I went over the paper. There is hardly anything about how they determined the accuracy of the distance measurement. It's nearly all about timing accuracy.

I did find this statement on page 9:

"and by transposing their positions with a terrestrial traverse down to the OPERA detector."

I think that means people with theodelites.

 

Offline JP

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Faster than light neutrinos?
« Reply #27 on: 24/09/2011 02:32:20 »
Yeah, they said something similar in the talk.  I have no idea how much error a "terrestrial traverse" causes.
 

Offline Geezer

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Faster than light neutrinos?
« Reply #28 on: 24/09/2011 05:24:58 »
Yeah, they said something similar in the talk.  I have no idea how much error a "terrestrial traverse" causes.

Hopefully not much! It would be a bit embarrassing if the whole business was mucked up by a bit of sloppy surveying. Considering how critical the path length measurement is, I was a bit surprised that they don't go into it in a lot more detail. That's likely to be the thing skeptics (like me) pounce on first.

We'll have to wait and see if similar results can be produced elsewhere.
 

Offline Soul Surfer

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Faster than light neutrinos?
« Reply #29 on: 24/09/2011 09:40:33 »
They must have a reasonable confidence that their measurement accuracies are sufficient to allow this time difference to be quoted and with modern kit it should be well within a foot over this distance.  Let us have a think about other reasons why there might be a small difference. 

Firstly from supernova 1987a  where a neutrino pulse was measured we have good evidence that neutrinos travel through EMPTY SPACE at very close to the velocity of light.  The  velocity error observed in the experiment is 4 parts in 10,000.  This supernova was around 160,000 light years away so if the velocity error was that great through empty space  the neutrino pulse would have come  ABOUT FOUR YEARS before the light pulse appeared!  Instead it was in effect just a few days before.  Just about the time that it would take for the explosion to blow up the star big enough to be recognised as a supernova.

Could it then be that neutrinos travel faster through dense matter than empty space.  that is the refractive index for neutrinos is negative.   How could this possibly be.

Now solid matter consists mostly of empty space together with nucleons which the neutrinos also have to pass through  now the nucleons represent only a tiny part of the matter.  funnily enough this is around one part in 10.000 of the size of the atoms so if in effect the neutrinos travel through this material "faster" (I use the inverted commas with intent) this might just be possible.

Could this in effect be done without contravening the normal rules about the velocity of light?

Well maybe because particles are always waves as well and if travelling through a nucleon causes a phase change in the wave it might well be possible that the apparent "position" of the neutrino is changed and moved ahead of where it might be expected to be if the nucleon was not there and this could integrate into a significant time on a long journey through solid material.

This means that the basic laws of physics are not affected but it might have some interesting effects when it comes to modelling pulses of energy flow in condensed objects like neutron stars.
 

Offline lightarrow

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Faster than light neutrinos?
« Reply #30 on: 24/09/2011 13:05:09 »
Someone says the statistical interpretation of the experiment is wrong:
http://johncostella.webs.com/neutrino-blunder.pdf
 

Offline Geezer

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Faster than light neutrinos?
« Reply #31 on: 24/09/2011 16:53:59 »
Someone says the statistical interpretation of the experiment is wrong:
http://johncostella.webs.com/neutrino-blunder.pdf

Thanks Lightarrow! Very interesting.

Reducing 16,000 events with a tolerance of 10.5 microseconds to a probable tolerance of 6.9 nanoseconds obviously requires very careful analysis.
« Last Edit: 24/09/2011 19:04:51 by Geezer »
 

Offline JP

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Faster than light neutrinos?
« Reply #32 on: 24/09/2011 20:34:55 »
Someone says the statistical interpretation of the experiment is wrong:
http://johncostella.webs.com/neutrino-blunder.pdf

Thanks Lightarrow! Very interesting.

Reducing 16,000 events with a tolerance of 10.5 microseconds to a probable tolerance of 6.9 nanoseconds obviously requires very careful analysis.

And the paper says virtually nothing about how they calculate statistical error...
 

Offline Jan Bruggers

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Faster than light neutrinos?
« Reply #33 on: 24/09/2011 22:06:12 »
It is given that the speed of light is a barrier which is infinitely high. Up to now all experiments has proven this. But if that barrier is not infinitely high than accordance the very basis of quantum mechanics particles have a transmission change (T). For a square potential barrier a good approximation T=exp(-2Ba) where  B =((Vo-E)2m/h^2)^0.5, Vo is barrier hight, h must be h-bar. Still the barrier is extreem high but not infinitely. Is this possible ?
 

Offline Soul Surfer

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Faster than light neutrinos?
« Reply #34 on: 24/09/2011 23:53:10 »
I think that the refutation of statistical accuracy paper found by light arrow is very plausible and they are pushing their theoretical accuracy far too far
 

Offline JP

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Faster than light neutrinos?
« Reply #35 on: 25/09/2011 15:32:20 »
I think that the refutation of statistical accuracy paper found by light arrow is very plausible and they are pushing their theoretical accuracy far too far

It was plausible, but it had an error.  John Costella has a new paper up (same link) that explains his error and why they were right about their uncertainty...
 

Offline Geezer

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Faster than light neutrinos?
« Reply #36 on: 25/09/2011 17:46:45 »
I think that the refutation of statistical accuracy paper found by light arrow is very plausible and they are pushing their theoretical accuracy far too far

It was plausible, but it had an error.  John Costella has a new paper up (same link) that explains his error and why they were right about their uncertainty...

The plot thickens  ;D
 

Offline neutrino

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Faster than light neutrinos?
« Reply #37 on: 25/09/2011 23:40:13 »
Maybe this also blows away the theory that an object traveling at the speed of light increases in mass?
"as an object approaches the speed of light, the mass increases without limit"

and even though the mass of a  Nuetrino is extremely small - it would still increase.. to what degree???
wonder if they can detect any change in mass ( another experiment perhaps!)

But this question of light speed..... is it truly a Limit!? or just that we'v found nothing that exceeds it! ( until now that is! ) 
Speed and time dilation - perception of time changing - or factual time change when getting to speed of light or greater.. could this be the explanation?
 you go faster than the speed of light, and a "time" shift takes place!? 
but then again - does time exist? isn't it simply a measurement we devised to keep track of one day to the next, one moment to the next, a means to reference something that took place in the past, and something that will take place in the future.
"Time"  is of no consequence to the physics of the universe,  it's little more than as said, a means by which WE measure one  moment to the next?   ???
 

Offline Soul Surfer

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Faster than light neutrinos?
« Reply #38 on: 25/09/2011 23:55:09 »
I have to agree with what is said in the new analysis but I am still a bit unhappy about pushing the accuracy so far and the fact that only the results right at the edges of the 10 microsecond pulse are critical.

I would feel happier if it were possible to extract some details of the fine structure of the main body of the beam (mentioned in the main paper)  from the results and by using crosscorrelation show that the timing of this also demonstrated the same time of flight measurements.  This would then show that there was not some other unknown process causing any blurring of the results.
 

Offline MikeS

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Faster than light neutrinos?
« Reply #39 on: 26/09/2011 06:43:38 »
Maybe this also blows away the theory that an object traveling at the speed of light increases in mass?
"as an object approaches the speed of light, the mass increases without limit"

and even though the mass of a  Nuetrino is extremely small - it would still increase.. to what degree???
wonder if they can detect any change in mass ( another experiment perhaps!)

But this question of light speed..... is it truly a Limit!? or just that we'v found nothing that exceeds it! ( until now that is! ) 
Speed and time dilation - perception of time changing - or factual time change when getting to speed of light or greater.. could this be the explanation?
 you go faster than the speed of light, and a "time" shift takes place!? 
but then again - does time exist? isn't it simply a measurement we devised to keep track of one day to the next, one moment to the next, a means to reference something that took place in the past, and something that will take place in the future.
"Time"  is of no consequence to the physics of the universe,  it's little more than as said, a means by which WE measure one  moment to the next?   ???

If this were true why is it that atomic clocks can measure time dilation due to the strength of gravity varying.  The latest with an accuracy of 18 decimal places can measure as little a one millimetre in difference in height.  If time wasn't 'real' all clocks would measure the same going rate everywhere.
 

Offline MikeS

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Faster than light neutrinos?
« Reply #40 on: 26/09/2011 07:06:33 »
If the neutrinos were going faster than light then they would be going backwards in time.  This would allow them to arrive before light(?).  The time shift would be distance dependant. It would be interesting if a similar experiment were carried out elsewhere but at a different distance.  Seems to me the effect is most likely due to some unaccounted for error.
 

Offline Geezer

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Faster than light neutrinos?
« Reply #41 on: 26/09/2011 09:35:56 »
I still say they managed to fubar the distance, for no other reason than it appeals to my sense of the absurd  ;D
 

Offline Soul Surfer

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Faster than light neutrinos?
« Reply #42 on: 26/09/2011 10:14:25 »
I don't think that anything anomalous does happen on the normal atomic scales but things could very well be different down in dense material (nucleons etc) down at the scale defined by the strong interaction.  This may be one of the very few ways that we could measure these effects because it involves scales of 10^-15 metre and times around the time it take light to travel that distance  ie 10^-23 second.  Remember many cosmologists consider that at very close to the instant of the big bang the velocity of light is in effect infinite.

One of the other things that I have been considering is that quantum mechanical uncertainty is involved in these interactions and this greatly increases the "random noise" in the experiment.  However I cannot see how this could introduce any bias, only a great deal more variation within which this result would be a statistically typical result.   One of the ways this might be tested is to take say four our five subset groups of the results taken at various times and analyse them independently to see if they all individually show traces of this bias.
 

Offline syhprum

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Faster than light neutrinos?
« Reply #43 on: 30/09/2011 10:21:27 »
is it possible that the true value of c is determined by the speed at which neutrinos travel and that photons travel slightly slower than c ?
Does this mean that we have to redefine the meter ?
« Last Edit: 30/09/2011 10:34:15 by syhprum »
 

Offline imatfaal

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Faster than light neutrinos?
« Reply #44 on: 30/09/2011 10:50:19 »
I don't think so for either case.  the speed of light pops out of maxwell's equations and is fundamental to SR - so if neutrinos go faster then they do; but it does not affect c.  the metre is merely an arbitrary distance - the fact that it is tied in the speed of light in its definition does not mean that it depends on the speed of light for its measurement.  as a mad example - if the great flying spaghetti monster changed by fiat the speed of light to 300,000,000 m/s exactly - we would not change the length of our metres, we would merely redefine the metre to the distance light travels in 3*10^-8 sec (or maybe something else entirely, less at the whim of a mad god)
 

Offline yor_on

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Faster than light neutrinos?
« Reply #45 on: 30/09/2011 13:10:00 »
There will be found to be something weird involved here, either a mistake of some kind, or 'tunneling' 'backward time travel' 'distance shrinking' whatever. But I'm willing to bet that it won't change 'c' as the constant it is, also that it won't mean that we ever will be able to 'time travel' backwards..
 

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Offline butchmurray

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Faster than light neutrinos?
« Reply #46 on: 04/10/2011 23:07:16 »
Shrunk
Ocam would also tell us that gravitational forces are speeding the acceleration of the expansion of the universe. But since we know what gravity is and that it could cause something very much like we are experiencing if the sources were in the correct positions and they could be the hiding places of the missing mass it would be too easy. So let’s come up with some negative gravity or dark energy and think of something else whimsical to answer the mass question. That’s the way we roll!

Too cynical?

 

Offline MikeS

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Faster than light neutrinos?
« Reply #47 on: 06/10/2011 07:28:19 »
Presumably the neutrino beam was made up of both neutrinos and anti-neutrinos?
If so then it is certainly conceivable that the anti-neutrinos were going backwards in time which would make them appear to be going faster than the speed of light.
 

Offline imatfaal

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Faster than light neutrinos?
« Reply #48 on: 06/10/2011 10:55:22 »
Mike - the paper only mentions neutrinos (but it would as the timing would be identical).  the neutrinos were formed by decay of pions (and kaons)

π+ -> μ+ + νμ

π- -> μ- + antiνμ

Frankly I cannot find which form was happening - and as neutrinos are uncharged they could be their own anti-particle - does it really matter.



 

Offline MikeS

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Faster than light neutrinos?
« Reply #49 on: 06/10/2011 11:48:47 »
Mike - the paper only mentions neutrinos (but it would as the timing would be identical).  the neutrinos were formed by decay of pions (and kaons)

π+ -> μ+ + νμ

π- -> μ- + antiνμ

Frankly I cannot find which form was happening - and as neutrinos are uncharged they could be their own anti-particle - does it really matter.





If they are their own antiparticle then no it does not matter.  However, if they are not their own antiparticle, if they have mass for example then conceivably they could be going backwards in time in which case it would matter, a lot.
 

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Faster than light neutrinos?
« Reply #49 on: 06/10/2011 11:48:47 »

 

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