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The experimental results suggest that neutrinos are "Faster than light". Why is that?

Swiss watches are better than Italian watches.
2 (12.5%)
It turns out the Swiss meter is slightly different from the Italian meter.
0 (0%)
Systematic computational error
2 (12.5%)
Neutrinos "tunnel" faster than light through atomic nuclei.
2 (12.5%)
Previously unknown gravitational anomaly
2 (12.5%)
Safely grazing sheepies used magic to speed up neutrinos
1 (6.3%)
Too many adult beverages
2 (12.5%)
The Earth is more curved than we thought
0 (0%)
Any mass with very high energy can travel faster than light.
1 (6.3%)
There is only one neutrino that travels infinitely fast and is thus everywhere at once
1 (6.3%)
A missing delay in electronics or a problem of synchronization with satellites
0 (0%)
It's not the neutrinos that are fast, it's the photons that are slow
1 (6.3%)
Neutrinos are allowed to take shortcuts through one of the other 7 dimensions
1 (6.3%)
The neutrinos were being chased by Zurich gnomes
0 (0%)
Insufficient slide-rule lubricant
1 (6.3%)
Some of the Swiss neutrinos were unknowingly entangled with Italian neutrinos
0 (0%)
Surveyors were beguiled by sheep
0 (0%)
The technicians cocked it up and the scientists are going to make sure they take the heat.
0 (0%)

Total Members Voted: 16

Author Topic: Why don't OPERA Gran Sasso results comply with current knowledge?  (Read 21456 times)

Offline Geezer

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BTW I think information travels faster in the type of optical cable used for long distance circuits that it does in coaxial cable. best check

You're right. I'm being a bit pessimistic.
 

Offline Bill S

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I voted for "There is only one neutrino that travels infinitely fast and is thus everywhere at once" because I like the idea of someone else bringing infinity into the discussion.  ;D

However, I also quite like the thought that they may have found the long soughtafter tachyon.  Can we be sure that neutrinos don't always travel just a little faster than light.

Hang on, though, shouldn't that mean they travel backwards through time?
 

Offline imatfaal

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I voted for "There is only one neutrino that travels infinitely fast and is thus everywhere at once" because I like the idea of someone else bringing infinity into the discussion.  ;D

However, I also quite like the thought that they may have found the long sought after tachyon.  Can we be sure that neutrinos don't always travel just a little faster than light.

Hello Bill - welcome back. 

The neutrinos from Supernova SN1987a got to earth at the correct predicted time - ie a few hours (not years) earlier than the light; the light has to contend with the gas/dust cloud surrounding a huge exploding star, the neutrinos whip straight through.  So at present we think neutrinos travel at a significant proportion of the speed of light  (99.9 and more nines)

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Hang on, though, shouldn't that mean they travel backwards through time?
You cannot have Special Relativity, Faster than Light, and Causality all at the same time.  So we would say that for some reason these neutrinos do not seem governed by Special Relativity - this is a bit of a blow, but not too bad.  Sr is already limited to flat space so another limit ain't that bad
 

Offline Bill S

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You cannot have Special Relativity, Faster than Light, and Causality all at the same time.

Confused!!! Are you saying that if something could travel faster than light, it would not travel backwards through time?

Thanks for the "welcome back".  I hope to have a little more spare time for asking silly questions, at least for a while.
« Last Edit: 15/12/2011 17:15:07 by Bill S »
 

Offline simplified

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I exactly don't  know how scientists create right formulae.But now I think it is impossible to create formula of energy of  such fast massive object, because we are  captives of relative kinematic slowing of time. Development needs an experiment with a synchronization of atomic clocks on a satellite.
 

Offline imatfaal

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You cannot have Special Relativity, Faster than Light, and Causality all at the same time.

Confused!!! Are you saying that if something could travel faster than light, it would not travel backwards through time?

Thanks for the "welcome back".  I hope to have a little more spare time for asking silly questions, at least for a while.

What I am saying is that the failure of causality, ie the travelling backwards in time, is a result of plugging FTL speeds into the ideas of special relativity.  BUT SR does not deal with massive objects going light speed and deals with nothing going FTL.  You cannot extrapolate SR into a realm of FTL travel because SR has an axiom that speed limit is that of light.  I do not know what happens if you could get a massive object above SoL - but I am sure that you cannot use SR to predict it. 

Personally I think that FTL travel is not feasible and OPERA Gran Sasso has made a mistake.  The Yanks are repeating the experiment in Fermilab/MINOS - and iff that comes in with agreement to OPERA then all bets are off - but I just don't think it will
 

Offline simplified

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Quote
You cannot have Special Relativity, Faster than Light, and Causality all at the same time.

Confused!!! Are you saying that if something could travel faster than light, it would not travel backwards through time?

Thanks for the "welcome back".  I hope to have a little more spare time for asking silly questions, at least for a while.
.  The Yanks are repeating the experiment in Fermilab/MINOS - and iff that comes in with agreement to OPERA then all bets are off - but I just don't think it will
Your forecast  may be wrong again.Because massive object with very high energy can move some space. :P
 

Offline simplified

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Hi Imatfaal. Let's consider Einstein's formula of speed
          v=[c (E^2+2Emc^2)^1/2]/(E+mc^2)
v - speed of massive object
E - kinetic energy of the massive object
m - mass of the object
c - light speed

I suspect that if we  insert  very big energy and very small mass then speed can be more than light speed. But my calculator is unable precisely to count such numbers . :-\
 

Offline simplified

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   :( I am wrong because
                                 ( E^2+2Emc^2)^1/2 < (E^2+2Emc^2+m^2c^4)^1/2
 

Offline CliffordK

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I tried to figure out which were actually bigger, neutrinos, or photons thinking that speed was related to mass.  However, I think the neutrinos are actually slightly larger than the photons.

With stellar phenomena, different energy photons (wavelengths) including Gamma all arrive at Earth at the same time.  So energy alone doesn't account for the difference of speed.

There also seems to be a rather high error rate in the measurements.  One question related to other discussions.  Essentially all of our current measurements of the speed of light are "2-way" measurements.  The speed from the source to a mirror and back. 

One should be able to do good one-way speed of light experiments using geosynchronous satellites, but I'm not sure if these have been done. 

Anyway, perhaps the neutrino experiments are one-way speed experiments that would be biased by the time of day they are being collected (and thus Earth's orientation in space).
 

Offline imatfaal

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I tried to figure out which were actually bigger, neutrinos, or photons thinking that speed was related to mass.  However, I think the neutrinos are actually slightly larger than the photons.
Larger?  Gotta be more specific.  For many years neutrinos were thought to be massless - this would mean they travelled at light-speed. It was later found that due to the strange oscillation of the neutrino between the different flavours (electron, mu and tau) that they must have a finite mass.  As they do have mass they cannot travel at the speed of light - especialy not at above the speed of light 

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With stellar phenomena, different energy photons (wavelengths) including Gamma all arrive at Earth at the same time.  So energy alone doesn't account for the difference of speed.
of photon.  but we do not know this is the case for neitrinos.  to reconcile opera/gran sasso with SN1987a there must exist neutrino of certain energies that travel at a fraction (below 1) of the speed of light

Quote
There also seems to be a rather high error rate in the measurements.  One question related to other discussions.  Essentially all of our current measurements of the speed of light are "2-way" measurements.  The speed from the source to a mirror and back. 
  The errors in the measurements seem pretty robust at the moment and any glaring mistakes would have been well publicised.  many of the claimed errors after the opera/gran sasso announcement turned out to be erroneous!

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One should be able to do good one-way speed of light experiments using geosynchronous satellites, but I'm not sure if these have been done. 
  OK - I would have to read up on that, not sure I know what you mean

Quote
Anyway, perhaps the neutrino experiments are one-way speed experiments that would be biased by the time of day they are being collected (and thus Earth's orientation in space).
  Not sure I quite understand what you mean - FYG the experimental data was collected over many days and at different times.  I would have hoped that any diurnal anomaly would have been spotted very early on. 
 

Offline David Cooper

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Are the neutrinos also travelling faster than the speed of light as it would be outside of the Earth's gravity well, or are they only travelling faster than light in the sense that they're going faster than light that's being slowed by the Earth's gravity?
 

Offline CliffordK

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Whew!!!
Ok, Ok, Ok.

With mass, there seems to be some odd units, generally in eV (or energy, I think).
Photon Mass: <1×10−18 eV/c2
Neutrino Mass: between .2 eV and 2eV
So...  can we equate energy and mass?  Unless speed can account for energy differences?

Ahh, I think I had misinterpreted this from Wikipedia

So, this is difference between the Neutrino speed and the calculated speed of light for 20 tests.  All show the Neutrinos going faster than light, but range from difference of 40ns to 90ns faster than light.  It still is a fairly wide range, and doesn't really seem to follow a "Normal Distribution", at least with the number of trials in the image.

Yes, it does sound like the experiment was being run 24 hrs a day.  However, only the results from 20 neutrinos were used, I think...  When?

One should compare these results with cosmological neutrino sources.  For example, a supernovas generate a pulse of both neutrinos and light.  Not necessarily at the same time, but one would expect if they were traveling at the same speed, that the photons and Neutrinos would arrive similarily for supernovas 1 thousand lightyears away and those 1 million lightyears away

Now...
For one-way speed of light.  It is a big issue.
Here is the Michelson–Morley experimental setup:
http://en.wikipedia.org/wiki/Luminiferous_aether
http://en.wikipedia.org/wiki/Michelson-Morley_experiment

The problem is that if you consider the frame bound, one-way speed of light to be:
C+X/C-X in the X direction, and C+Y/C-Y in the Y direction.
Then, the Michelson-Morley bounces light all over...  but it all comes down to every X+ is countered by an X-.  Every Y+ has an equivalent Y-.  At best, all the experiment demonstrates is that the two-way average speed of light, C, is the same in both the X and Y directions which could be demonstrated with a much simpler design.

Obviously the issue is to create a device big enough with a high enough shutter speed to measure the one -way speed of light (in two directions), with the definition, of course, being in a vacuum.



I believe that one could create a wheel shutter device that would do reasonably well at measuring the speed differential between the one-way speed of light.  X+ & X-.  The problem is that it would be difficult to get the accuracy necessary.  But, perhaps in the near future, with higher speed motors and better magnetic bearings, it will be possible to construct such a device that is a few meters long.

Here is where I presented my concept for 1-way light speed measurements using satellites.

http://www.thenakedscientists.com/forum/index.php?topic=42756.msg377479#msg377479

To avoid redundant arguments, I'll refer you to that post.  The idea is that every 12 hours, the relative positions of satellites A&B reverse.  So, timing errors cancel out.


 

Offline imatfaal

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Whew!!!
Ok, Ok, Ok.

With mass, there seems to be some odd units, generally in eV (or energy, I think).
Photon Mass: <1×10−18 eV/c2
Neutrino Mass: between .2 eV and 2eV
So...  can we equate energy and mass?  Unless speed can account for energy differences?
Energies can be given in eV (electron volts) - due to mass energy equivalence we can measure masses in eV/c2.  The c2 is nearly always missed off because in most particle physics we use more natural units in which we put the speed of light as equal to one.



Quote
Ahh, I think I had misinterpreted this from Wikipedia

So, this is difference between the Neutrino speed and the calculated speed of light for 20 tests.  All show the Neutrinos going faster than light, but range from difference of 40ns to 90ns faster than light.  It still is a fairly wide range, and doesn't really seem to follow a "Normal Distribution", at least with the number of trials in the image.
  I don´t think that 20 results are enough to say what sort of distribution


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Yes, it does sound like the experiment was being run 24 hrs a day.  However, only the results from 20 neutrinos were used, I think...  When?
  20 results refers to the retest done in October - with the very short bursts to overcome any problem of phase-shifting

Quote
One should compare these results with cosmological neutrino sources.  For example, a supernovas generate a pulse of both neutrinos and light.  Not necessarily at the same time, but one would expect if they were traveling at the same speed, that the photons and Neutrinos would arrive similarily for supernovas 1 thousand lightyears away and those 1 million lightyears away
  Been done - that was why I mentioned trying to consolidate results from Gran Sasso and SN1987a (Supernova 1987 a).  The neutrinos from that Supernova arrives a few hours ahead of the light - which would be expected as they do not have trouble get through the gas/dust/etc surrounding the Supernova.  If they travelled at the Gran Sasso speed they would have been here years earlier.


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Now...
For one-way speed of light.  It is a big issue.

/snipped for now - will have a look later

« Last Edit: 13/01/2012 10:22:52 by imatfaal »
 

Offline CliffordK

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Ok,
The experiment that I described with geostationary satellites essentially is an East/West experiment in the plane of the Earth.  That should detect the frame-drift of the speed of light in Earth's plane which would reverse on a 12 hr (sidereal) period.

The OPERA Gran Sasso experiment is more or less a North/South experiment.

So, in a 24 hour period, the installation would more or less describe a cone in space.  Thus, you wouldn't get the reversal that I had suggested.

If there was a positive frame-shift in the speed of light, then one would see it waxing and waning with the timing of the direction based on the sidereal day.

Plotting the times on a sidereal day should generate a sine wave. 
Plot the hours of the sidereal day on the X axis, and the speed differential on the Y axis.
« Last Edit: 14/01/2012 17:23:53 by CliffordK »
 

Offline Geezer

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I added a new voting option.
 

Offline imatfaal

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I added a new voting option.

The techies will now dig out a memo they sent 10 years ago complaining about cheap components and lack of staff to check connexions - that the boffins passed to the bureaucrats with an exasperated sigh - and it can all be blamed on management, who will then give themselves a pay rise to make sure they pay more attention next time.
 

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