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#40229 09/19/11 05:27 PM
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Ok I will post a link from Tommaso Doringo for those who haven't seen it

http://www.science20.com/quantum_diaries_survivor/sixsigma_signal_superluminal_neutrinos_opera-82744

Personally I am with Tommaso I really doubt it and CERN has delayed the release to check the data.

If this stands we have new physics ... something faster than the speed of light has been recorded for the first time.


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orac, I can't find that one. I clicked on the link and it took me to the home page at Science 2.0 and I can't find anything on there about superluminal neutrinos.

It sounds interesting, but off of the top of my head I agree with you. It is unlikely.

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I had the same problem, Bill, but found lots of other interesting things.


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Ahh Tommaso is a CDM colaborator he had to take it down I see ... you will have to wait until Friday for the official release by looks.

Here is Lubus going to town on the result which is about all that's left up at the moment .. alot of which I agree with but would have been nicer about it.

http://motls.blogspot.com/2011/09/italian-out-of-tune-superluminal.html

Last edited by Orac; 09/20/11 02:13 AM.

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Adding in some clarifications:

Luboš Motl clarified Tommaso is employed by IFNF which also pays for Opera so it’s a clash of interest for him to talk about unpublished Opera’s results so he has taken down the webpage.

http://blog.vixra.org/2011/09/05/2691/

Quote:

Update 20-Sep-2011: Neither of the Higgs seminars discussed any new data beyond that shown at Lepton-Photon 2011. The Santander workshop is proceeding with no slides being posted online so far. We are waiting for the OPERA neutrino seminar of Friday where the growing rumour says they will report the discovery of tachyonic neutrinos.


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I have seen several discussions about this so far. Most are rather skeptical. A couple have also pointed out that when supernova 1987A was spotted that a group of neutrinos was detected about 3 hours earlier than the light. They explain this by the fact that the neutrinos from the explosion left the star immediately upon creation. The light had to travel through the mass of the star before it could start on its journey. The best timing they can get showed that the neutrinos traveled very slightly faster than light. Most people didn't put much faith in the value being faster, because of uncertainties in the measurement. But, the amount that the supernova neutrinos traveled faster than light was much much smaller than the amount claimed with the OPERA experiment. And the error bands don't even start to overlap. So most have decided to have serious doubts about the reality of the OPERA data.

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Okay the conferences and discussion roll on

http://www.physorg.com/news/2011-09-cern-faster-than-light-particle.html

What does give me confidence is those who have recorded the findings don't like them either and want others to check the measurement.

So lets take a leap of faith and discuss what are the options for how such a result can come about.

First you need to know Nuetrinos are weird you perhaps need to do some background on them (http://en.wikipedia.org/wiki/Neutrino).

One of the most weird part about Nuetrinos is there flavours and oscillation (http://en.wikipedia.org/wiki/Neutrino_oscillation).

Okay so lets look at the 3 possibilites I see feel free to throw in thoughts.

1.) QM Lorentz-violation effect

QM predicted that nuetrinos may infact travel faster than light because of the weird oscillation by a process called lorentz-violation (http://en.wikipedia.org/wiki/Lorentz-violating_neutrino_oscillations). The problem this creates for physics is QM is more fundemental than the physical world something always strongly resisted by many scientists and many of you :-)


2.) Tachyonics is real and possible (http://en.wikipedia.org/wiki/Tachyon). The posibility of Nuetrinos being tachyonic was discussed Alan Chodos in 1985 as a test of tachyonics (http://adsabs.harvard.edu/abs/1985PhLB..150..431C).
The dislike of tachyonics is along the similar lines to QM above it gives GR/SR causality problems as all the discussed time paradoxes come into being. This may be less of a hassle these days as QM to some degree has closed these violations and if you accept the QM Novikov self-consistency principle (http://en.wikipedia.org/wiki/Novikov_self-consistency_principle) they are completely closed.


3.) We are looking at some weird new physics. The books open on this one throw in your thoughts.

EDIT: WOW the story is everywhere now dominating most of the physics discussions. Quite strange watching a result a few of us were quietly discussing going to headlines around the world.

Last edited by Orac; 09/23/11 06:52 AM.

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I've not had time to follow up on Orac's links yet, so this might be covered somewhere. If these results are right, and SR prohibits a subluminal object from becoming superluminal, presumably, these neutrinos always travel faster than light.

Does this mean we've found the tachyon?

If so, should they not be travelling backwards through time????


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Can someone explain the animation shown at http://en.wikipedia.org/wiki/Tachyon.

Elsewhere, we had a discussion about what, if any, interaction two observers could have if they were travelling in opposite directions through time. I think we, more or less, reached a point where we were saying that their interaction would be limited to 10^-43s; not really long enough to "see" anything.


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Tomasso has put the original links back up now

http://www.science20.com/quantum_diaries_survivor/sixsigma_signal_superluminal_neutrinos_opera-82744

The paper is up although understandably slow downloading (http://arxiv.org/abs/1109.4897)

Quote:

The OPERA result is based on the observation of over 15000 neutrino events measured at Gran Sasso, and appears to indicate that the neutrinos travel at a velocity 20 parts per million above the speed of light, nature’s cosmic speed limit.


It's rather hectic today running from meeting and group discussion and online presentations.

http://www.physorg.com/news/2011-09-scientists-stunned-sceptical-faster-than-light-particles.html

People stunned is a fair comment because CERN have actually done alot of checks they have know of the result for months.

From what people say this actually matches closely the original FTL claim from the supernova which was subsequently explained away by saying the nuetrinos were emitted earlier than the light.

Lubos and probably alot of the string theory boys are banking on a media density effect but the QM groups have a vastly different take.

For Bill S most in QM are definitely favouring nuetrino oscillation because it's only just above the speed of light not miles above (http://en.wikipedia.org/wiki/Lorentz-violating_neutrino_oscillations).

Quote:

The unconventional energy dependence in the theory leads to other novel effects, including corrections to the dispersion relations that would make neutrinos move at velocities other than the speed of light. By this mechanism neutrinos could become faster-than-light particles.


The big question can we match theory to numbers!

Well got to get back to it ... will post more when I know a bit more.

Last edited by Orac; 09/23/11 01:22 PM.

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http://www.scienceagogo.com/news/20110822191734data_trunc_sys.shtml

"If true, the results will open up new physics in which Einstein's relativity doesn't hold true."

Would we still fave to throw out SR if these neutrinos always travel at superluminal speed?


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BTW, Orac, it's good to have someone on the Forum who is so close to the centre of activity.


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Close ... not close enough :-)

I am sure most physics research uni's are the same the real work is with CERN, fermi etc which many of us have friends in as you probably figured that out already.


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Have they checked to make sure which direction the detected neutrino was travelling?

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Originally Posted By: Planko
Have they checked to make sure which direction the detected neutrino was travelling?


I assume you are thinking about the question of which way it might have been travelling through time. If it was going backwards in time it would be observed at Gran Sasso first, then at CERN. It's not as straightforward as that, though. To be observed at all, the two time frames would somehow have to co-incide.


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BTW, the thread "Communication across time" contains a discussion of this sort of problem.


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Okay I have read and discussed superluminal nuetrinos to death over the last week .. so what have I learnt and what do I think.

Well to me the result is an odd ball and it doesn't sit well with any of the predicted theories .... but I am willing to make one of two bets based on the data.

So here is my take for what it's worth to people interested.

Biggest weirdo for me is the speed variance is not effected by the energy levels of the nuetrinos. The energy of the neutrinos have a fairly wide spread so I would expect the speed to vary but no such dependency was observed. Most physical effects you could imagine would have an energy dependence of some sort, okay it may be so small we can't see it but that in itself is weird why is it so small. Even within QM effects it would expect a difference between higher energy netrinos and lower.

To me the result alone for me says there is one of two options a systemic measurement error (they made a mistake) or that the effect is outside "normal" physics of light and particles.

Such weird physics outside normal physics is known and more importantly to me it was one of the first to actually conclusively produced superluminal light => enter ... L. J. Wang, A. Kuzmich & A. Dogariu (http://www.nature.com/nature/journal/v406/n6793/abs/406277a0.html)

The inital reporting of this was met with howls that it had to be wrong nowdays we routinely accept it and teach it, here is a laymans version (http://www.msnbc.msn.com/id/3077368/ns/t...ins-rules-road/).

At the time this was sort of considered a parlor trick you needed to contrive very special setups to do it and it had never been seen in nature.

Gain-assist is a constant like refractive index it does not matter what the enrgies of the particles or photons entering and the noted result would be entirely consistant with it.

Now what I am asking myself is what we are seeing a gain-assist of nuetrinos through matter (IE the earth). It's not very exciting for relativity or pseudoscience people who want superluminal speeds and GR/SR to be wrong but it is very very interesting to physicists none the less.

So my bets are down 50-50 for me

1). We have a systemic error that hasn't been identified
2). Nuetrinos see matter with a gain assist index.


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Originally Posted By: Orac
For Bill S most in QM are definitely favouring nuetrino oscillation because it's only just above the speed of light not miles above


Would the neutrino not have had to be travelling at superluminal speed from "birth"?


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Originally Posted By: Bill S.

Would the neutrino not have had to be travelling at superluminal speed from "birth"?


Yes Bill we know of no natural way that anything ever gets accelerated to it's speed ... we are the only ones who do that sort of thing :-)

Sub-Atomic and photon particles are born at whatever speed they do even if it was superluminal.

As I stated above I doubt the effect is QM because there is no energy dependancies that we can see.

We discussed that the nuetrino is thought to be two small virtual particles oscilating about a centre point. What exactly is the nature of this oscilation is the real curious part.

Now move to quantum tunneling and you will find quantun tunneling takes "no time" (http://rspa.royalsocietypublishing.org/content/460/2042/499.full.pdf).

So if the oscillation is a QM tunnel effect and that tunnelling was biased in some way along the axis of the travel path the particle would appear to micro jump the width of the oscillation.

The reason it was theorized it might be superluminal is because when you measure the spin of nuetrinos they are always left handed so there is some sort of bias.

Now there is alot of "ifs" in all that.

However the one consistancy you would expect is a higher energy nuetrino by definition "spins" faster and so if the above effect was real it should tunnel more often ergo it should appear to be even faster.

The absence of that effect is what I think is compelling against this explaination. It is true perhaps the bias is so small we can't measure the different energies doing different speeds but I would need convincing on that.

There is probably one last thing to add in where do thing go when they Quantum tunnel .... well thats a whole story right there .... extra dimension, dark matter, space "bulk", they just jump ... pick any story you like or make up your own :-)


Last edited by Orac; 09/29/11 03:50 AM.

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Originally Posted By: Orac
So if the oscillation is a QM tunnel effect and that tunnelling was biased in some way along the axis of the travel path the particle would appear to micro jump the width of the oscillation.


Would the extra movement in one direction not be balanced by extra movement in the opposite direction it the neutrinos were oscillating?


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Remember assuming the speed of light is fixed the sort of backward biasing won't occur that would be a movement effect if I am understanding what you are implying.

You have to think of this relativistically (http://en.wikipedia.org/wiki/Chirality_(physics))

Quote:

For massive particles—such as electrons, quarks, and neutrinos—chirality and helicity must be distinguished. In the case of these particles, it is possible for an observer to change to a reference frame that overtakes the spinning particle, in which case the particle will then appear to move backwards, and its helicity (which may be thought of as 'apparent chirality') will be reversed.


Quote:

A common source of confusion is due to conflating this operator with the helicity operator. Since the helicity of massive particles is frame-dependent, it might seem that the same particle would interact with the weak force according to one frame of reference, but not another. The resolution to this paradox is that the chirality operator is equivalent to helicity for massless fields only, for which helicity is not frame-dependent. For massive particles, chirality is not the same as helicity so there is no frame dependence of the weak interaction: a particle that interacts with the weak force does so in every frame.

A theory that is asymmetric between chiralities is called a chiral theory, while a parity symmetric theory is sometimes called a vector theory. Most pieces of the Standard Model of physics are non-chiral, which may be due to problems of anomaly cancellation in chiral theories. Quantum chromodynamics is an example of a vector theory since both chiralities of all quarks appear in the theory, and couple the same way.

The electroweak theory developed in the mid 20th century is an example of a chiral theory. Originally, it assumed that neutrinos were massless, and only assumed the existence of left-handed neutrinos (along with their complementary right-handed antineutrinos). After the observation of neutrino oscillations, which imply that neutrinos are massive like all other fermions, the revised theories of the electroweak interaction now include both right- and left-handed neutrinos. However, it is still a chiral theory, as it does not respect parity symmetry.

The exact nature of the neutrino is still unsettled and so the electroweak theories that have been proposed are different, but most accommodate the chirality of neutrinos in the same way as was already done for all other fermions.


If it isn't making sense yell and I will try and explain it. If you get passed understanding the left handedness it's a downhill run thats the hard part to get your head around usually.

This is alot like the issue I bought up with PreEarths two worlds spinning the forces align differently depending on there spin.

Ahh found a reasonable 3D approximation of spin the top graphic may help (http://hyperphysics.phy-astr.gsu.edu/hbase/particles/neutrino3.html)

Last edited by Orac; 09/30/11 03:53 AM.

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Thanks, Orac. It begins to make more sense now that I am not bogged down with the chemical version of Chirality. Still needs some more thought, though.


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Tommaso broke the story of possible superluminal nuetrinos now he breaks the first paper I have seen that at least provides consistancy with the result.

(http://www.science20.com/quantum_diaries...tivity_ok-83428)

That would mean the result is a derivative of the MSW effect which we actually discussed so my physics isn't completely destroyed :-)

Whilst it makes me feel happy that if the result is correct (and thats still a big if), I at least understand something of the process that creates the effect.

I like a few of the comments to the article still have a huge problem

>>> How does it avoid energy loss of known electroweak processes (e+ e- emission) <<<

First one to confirm superluminal nuetrinos and solve the energy problem get the Nobel prize :-)

Last edited by Orac; 10/11/11 06:24 AM.

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Quote:
where do thing go when they Quantum tunnel ....


Just another "plus" for the idea that QM gives us a window on the infinite. If the jump is in the infinite realm it needs no time, because there is no change.


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Originally Posted By: Orac
Ok I will post a link from Tommaso Doringo for those who haven't seen it

http://www.science20.com/quantum_diaries_survivor/sixsigma_signal_superluminal_neutrinos_opera-82744
...........>
If this stands we have new physics ... something faster than the speed of light has been recorded for the first time.

[quote=Mike Kremer]

Interesting discussion, I have not been around to pass any comments until now.

Orac states: "something faster than the speed of light has been RECORDED for the first time"
RECORDED is the operative word and extremely important in this context.

Because, if I might suggest--- The infinitesimal possible speed comparison between 'superluminal' Neutrinos and light speed measurements...is so minute...that the difference has not been detected before. Nor has there has there been any particular reason to check the specific speed of Neutrinos against light, until now?.
Nothing is faster than light ...its our basic physical law of the Universe...Einsteins Mantra.

Fact...the speed of light is slowed, or will speed up again, dependant upon the medium thru which it travels.

Fact, all the mathematics to do with the speed of light...are still correct, even when you input the speed of light as FASTER.
In this case the maths then correctly states that nothing can go SLOWER than the speed of light!

Since light speed differs according to the medium thru which it travels, however,Einsteins equations hold good, whichever part of the Universe or distant nebulae we look at.
Because the ultimate constant, we would require, to make any true measurement (overturn Einstein) would be DISTANCE.
Super accurate distance measurement, an impossibility I think.
Since we can never measure any very long distances, (part or light years apart),with enough accuracy
to enable us to then state the certainty of different speeds of particles moving thru different mediums.

The Micheleson Morley type of experiments come to mind. (Im not using this as a basis, since it used light only, and not
Light AND Neutrinos along the same path, and coming from the same point)
I want to show how difficult it will be to make an absolute measurement of particle/light speed. Dare I say impossible?
Just think of how many times they have checked the Neutreno/Light Speed measurement between Cern in Switzerland
and the Lab in Rome, Italy.

I believe it was 500 or more times.....much of that checking the actual microscopic distance between the sending and receiving Lab instruments.
Even the heating of the Earth in sunlight, also the gravitational effect of the Moon will come into play, when one tries to measure the difference in SPEEDS of two Particles, a measurement that ultimately depends upon absolute distance.

Who is to say whether the speed of light is any different when its moving AGAINST, (upstream) a powerful source of light, or 'downstream' together (parallel) with the main source.
Or more to the point ...any other type of Particle, or Graviton, moving towards and/or against its source or visa versa?
Can you visulise the hyper-theoretical particle the Graviton moving towards or against its source...and visulise its speeds?
Prehaps thats a little extreme for you, try using other particles ..does it makes you think?
Accurate measurement dependant upon the longest distance possible, its an absolute requirement just to check for the POSSIBILITY of particle speed differences.


.

.
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So, how do they measure the distance through solid rock?


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Originally Posted By: Bill S.
So, how do they measure the distance through solid rock?


They used the GPS system. Normally the GPS only gives accuracy within a few meters. But if you take many many readings and average them you can get quite good accuracy.

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Thanks Bill.

Would you not need more than "quite good accuracy" to measure something as small as the difference between "c" and the speed of these neutrinos?


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Originally Posted By: Bill S.
Would you not need more than "quite good accuracy" to measure something as small as the difference between "c" and the speed of these neutrinos?

It depends on your definition of "quite good accuracy". My definition is "good enough for the job on hand". If I'm on an interstate highway "good enough" is probably on the order of a couple of miles. If I'm trying to measure the speed of neutrinos then it has to be a lot better.

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Quote:
It depends on your definition of "quite good accuracy".


I agree with your definition, Bill, but I would be inclined to think that achieving the accuracy necessary for this sort of measurement, using the GPS would qualify as "b....y good" smile


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Originally Posted By: MK
Fact, all the mathematics to do with the speed of light...are still correct, even when you input the speed of light as FASTER.
In this case the maths then correctly states that nothing can go SLOWER than the speed of light!


You've lost me here, Mike. I thought I knew what you meant first time, but having read it a few times I'm not so sure.


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Originally Posted By: Bill S.
I agree with your definition, Bill, but I would be inclined to think that achieving the accuracy necessary for this sort of measurement, using the GPS would qualify as "b....y good" smile


Well, it does require a lot of patience to get it that good. In fact it requires even more patience than it takes to just get a good reading. You have to keep doing it over and over, because of course the surface of the Earth isn't stable. For the kind of accuracy they need even very small changes in the Earth will affect the distance.

I know that the Earth shifts because one of the last projects I worked on before I retired was to find an automated way to determine true North for the inertial guidance package on the Delta IV Launch Vehicle. There is a standardized way they use on the Delta II which uses a theodolite to make several very precise measurements to determine the value to upload to the guidance system. But it is done the day before the launch, while they can still have people in the area of the vehicle. For some reason they don't want people close to the vehicle just before launch. Something about it being a hazardous location. Anyway they wanted a way to do the measurement in real time just before launch. I came up with several concepts of ways it might be done, but nothing with off-the-shelf equipment, so they attacked it from the other end and settled for the day before measurement.

The thing about this is that the measurement requires several precisely located points in the vicinity of the launch pad and they have to resurvey the site every year to make sure they haven't drifted. Now this was in Florida, which is not very seismically active, but is built on rather soft material that drifts pretty badly. The sites at CERN and OPERA are more stable, but I don't think they are stable enough to maintain their separation for all that long, at least not for the accuracy they need.

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It's one of those situations in which, the more one learns about it, the more amazing it seems that a degree of accuracy could be attained that would be sufficient even to lead to a suspicion that there might have been a speed difference.


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The paper was totally debunked there were huge cracks even in the comments if you read it.

The clocks are on the >>> ground <<<< and synchronized to the satelite and this is tested to 1 nanosecond. The paper assumes the clocks are up on the GPS satelites and thats the source of the papers error ... they aren't ... end of theory and FTL nuetrinos live for the moment.

Fermilabs is setting up to do confirmation or refuting the measurement and it's really pointless discussing it stuff until then probably other than more general speculation.


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I'm not sure what to think. There are a lot of criticisms in the comments section of the article. I can't follow them very well, but I suspect some of them don't know any more about it than I do. In any case, I note that Lubos commented and said,
'Well, this "paper" is equivalent to one paragraph of what I wrote on September 24th ... including the 30-nanosecond result.'

Which is not to say the paper is right.

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And that is the correct scientific approach. Suspect everything.

I don't accept the original result in the first place the only thing I am sure of the effect mentioned in that paper is not in play.

There may be other issues with GPS such as height etc I have seen a few papers.

Trust me if someone really debunks the FTL claim you will see it reported on every physics site.

Until we get another result in from Fermilabs probably not much else to comment on.


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Originally Posted By: Orac
And that is the correct scientific approach. Suspect everything.

I don't accept the original result in the first place the only thing I am sure of the effect mentioned in that paper is not in play.

There may be other issues with GPS such as height etc I have seen a few papers.

Trust me if someone really debunks the FTL claim you will see it reported on every physics site.

Until we get another result in from Fermilabs probably not much else to comment on.


Originally Posted By: Mike Kremer


Mike Kremer reads that..."...there is probably not much else to comment upon, unless we get further information-from Fermilabs"

I did mention in my previous post in this discussion-
That nobody has really had the need to measure the speed
of Neutrinos in the past.
Obviously every scientist in the World accepts the fact that Neutrinos travel at the speed of light.
Everyone accepts that, so the applecart remains stable and the World is saved. QED.

However after 500 re-tests by the Fermi lab, its obvious that something is wrong...which is why I suggested that maybe Neutrinos DID travel a tiny, tiny bit FASTER than light (since they must have re-checked and re-checked countless times.)

So here is my revised comment.

NO the NEUTRON DOES NOT travel FASTER than Light.
Its the Light that travels a teeny teeny bit SLOWER than the NEUTRON!!
(They have all got it wrong)

The calculated speed of the Neutron may well become the real actual speed of light,for all future calculations!!

Its the speed of light that we have all got wrong by a tiny tiny bit!!... Why???

BECAUSE nobody has ever calculated the REAL ACTUAL speed of light in a true Vacuum!!
Yes we have reflected it millions of times in a vacuum'd glass tube, using end mirrors.!
Yes we have measured the light from a star grazing the edge of a Planet! etc...etc.
BUT THATS NOT REAL DEFINITIVE MEASUREMENT is it?
I mean Neutrons pass thruu the Earth unimpeded, they are NOT affected by atmosphere, like light!!
NOT affected by Gravity like light!!
THEY are NOT affected by DENSITY, like LIGHT
Light SLOWS and gets tired as it travels across the UNIVERSE
Light being light is obviously affected by the density of of the medium it travels thru and many other things I would suggest.

YES we have the actual speed of light... from which every thing else is calculated from. Thus... Einstein and the Universe is vindicated and saved!!
And we all think we know the real speed of light??? I wonder??

Maybe the unaffected Neutron is the real actual speed of light.!!

And FERMI LABS have got it right, and might suddenly realise that -- the Speed of light as a constant, is just a tiny, tiny wee bit SLOWER that all the calculations have ever suggested.
The world is SAVED the Speed of light is actually the speed of the Easier to measure ubiqutous NEUTRON!!



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And checking all that is a fair call Mike but our first call will be to check the nuetrino speed.

CERN is going to send a tighter bunches of particles into the accelerator, Giving a much tighter time constraint on the neutrinos. The test will occur between 21 October to 6 November and expected to be seen between 10 and 15 neutrinos by opera.

So not a huge amount of data but very very tight release time. The clocks and distances have been checked so lets see what we get.

The only comment I don't agree with in your response

Originally Posted By: Mike

Light SLOWS and gets tired as it travels across the UNIVERSE


There is absolutely no observational or theoretical reason to believe light ever tires. It was an old unproven astronomical theory that is totally inconsistant with modern QM theory, Tired light would infact break QM.

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Dude, Tachyon is a hypothetical theory. No one knows it is true or not. And for neutrinos, particle physics actually says that tau and muon neutrinos faster than light. But you should know,it will have a whole bunch of complex number when you go through the mathematical stuffs(such as Lorentz factors).

I don't like it.

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I strongly doubt it is tachyonic much as Bill S would like it.

QM provides a much more simple and compelling way for it to occur called quantum teleportation and nuetrinos exhibit a weird oscillation that may make it possible.

But before we get all excited and ahead of ourselves we need confirmation of the speed and to do the sort of due diligence checks like Mike brought up.

Tachyonic behaviour should actually be rather easy to detect by comparison because it should exhibit an energy radiation trail which Icarus experiment doesn't see.


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Quote:
Tachyonic behaviour should actually be rather easy to detect by comparison because it should exhibit an energy radiation trail which Icarus experiment doesn't see.


Could it be that such a trail is not seen because it is travelling backwards through time?

Actually, I don't much like the idea of tachions, precisely because they are theorised as travelling backwards through time.


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Originally Posted By: Orac
And checking all that is a fair call Mike but our first call will be to check the nuetrino speed.


Originally Posted By: Mike Kremer


Wonderful..That seems to be in agreement with what i said in my previous post.



Originally Posted By: Orac

The only comment I don't agree with in your response



Originally Posted By: Mike

Light SLOWS and gets tired as it travels across the UNIVERSE

Originally Posted By: Orac

There is absolutely no observational or theoretical reason to believe light ever tires. It was an old unproven astronomical theory that is totally inconsistant with modern QM theory, Tired light would infact break QM.


Originally Posted By: Mike Kremer


Well I am amazed that that is the only comment you have made...In fact I was expecting quite a bit of Flak with my idea that the speed constant of the speed of light
is not sufficiently accurate for the purposes of this particular experiment.!!

That is why in my last post I made the 4 comments regarding the measurements of the speed of light.
I did say that Light is affected by a number of external influences on its journeys.

I made the comments "not so the Neutron." It is unaffected upon external influences. ...un-like Light.
I expected comments regading that idea.

I expected a lot of comments when i said I think the Neutrons speed was a better and more accurate substitute for the speed of light. ...Still no comments.
I said that it was Light that was actually going slower ...in relation to the measured speed of the neutron . and gave my reasons.. Still no comments.

I did say " Light SLOWS and gets tired as it travels across the UNIVERSE"
and got the only comment that light never tires. (thank you for that one comment)

Well maybe i should have said "Light SLOWS and reddens as it travels across the UNIVERSE"
Admittedley ..I go slower, tired, and redden if I exert myself at my age. Hehe.

So on the face of it prehaps every one agrees with my new proposal ..
That its the neutron that will give us the more accurate constant for the speed of light



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Quote:
Well maybe i should have said "Light SLOWS and reddens as it travels across the UNIVERSE"


Why would light need to slow and redden? Even if the tired light idea is correct, wouldn't the reddening be sufficient?


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Mike, your questioning our knowledge of the true speed of light prompted me to look back through my notes and unearth the following:

"....when we claim that the speed of light is well known, what we are really saying is that we know the speed of light relative to any observer, and since we have already established that such an observer can be travelling at any speed, or in any direction relative to the light, at the time of making the observation, then we must ask ourselves how well, in truth, we know the actual speed of light. Of course, if we are thinking relativistically, we also have to ask ourselves if talking about the actual speed of light is in any way meaningful.


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No Mike you miss your own point

The experiments to measure the speed of light were done by lasers in 1975 (http://en.wikipedia.org/wiki/Speed_of_light)

Quote:

After centuries of increasingly precise measurements, in 1975 the speed of light was known to be 299,792,458 m/s with a relative measurement uncertainty of 4 parts per billion. In 1983, the metre was redefined in the International System of Units (SI) as the distance travelled by light in vacuum in 1&#8260;299,792,458 of a second. As a result, the numerical value of c in metres per second is now fixed exactly by the definition of the metre.[5]


I am not going into your side issue but you do bring up a valid point how good was the 1975 measurement was there an error.

I am a scientist if the nuetrino number holds up I also need to check an error was not made in the 1975 work.

Remember the discrepency is very small.

As I said tired light breaks QM it is completely inconsistant with it. So if you want to have tired light you now need to propose a theory to replace QM because light can't be Quantized in a way QM proposes anymore and I have a pile of observations and experiments that need explaining.

Hence tired light has exactly zero traction in science and why I was struggling to even find references to it except historic.

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Quote:
Hence tired light has exactly zero traction in science and why I was struggling to even find references to it except historic.


Come back Bill 6, you must have something to sy about this!


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I predicted, in the Australian metaphysics journal 'Exposure' (October-November, 1996), that particles, such as neutrinos, that are projected toward the Earth's centre of gravity will travel faster than light.

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Originally Posted By: Bill S.
Quote:
Hence tired light has exactly zero traction in science and why I was struggling to even find references to it except historic.

Come back Bill 6, you must have something to sy about this!

I'm not sure if I raised this point previously - if a beam of light is projected through a sheet of glass the latter heats up.

The energy content of the emitted beam will be lower than that of the original beam hence the beam has lost some of its energy to the medium.

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Originally Posted By: Bill 6
I'm not sure if I raised this point previously - if a beam of light is projected through a sheet of glass the latter heats up.

The energy content of the emitted beam will be lower than that of the original beam hence the beam has lost some of its energy to the medium.


We did this dance and I showed you that effect is real but the heat up is caused by the loss of total photons which become the heat.

What we see is identical energy photons come out the glass and missing photons which equal the heat. What we never see is photons coming out with less energy or as you would call them tired.

BTW what was the reasoning behind a nuetron fired at the earths core being faster than light?


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Originally Posted By: Orac

We did this dance and I showed you that effect is real but the heat up is caused by the loss of total photons which become the heat.

What we see is identical energy photons come out the glass and missing photons which equal the heat. What we never see is photons coming out with less energy or as you would call them tired.

On the assumption that we have already done this dance, my response would most likely have been the same - when the atoms of the medium absorb the photons it is my understanding that the atoms then emit their own photons.

I see nothing there which indicates that the atoms totally absorb some of the photons.

If the increased temperature of the medium is due to a loss of total photons then the emitted light would incur a reduction in intensity.

In order for us to see that the emitted photons are of the same frequency as the original beam we would have to determine the frequency of both beams however the difference between them would be minimal to the point of being virtually indeterminable until we start talking about the considerable number of free atoms of matter scattered over vast tracts of space.

We have no way of determining the frequency of light emitted by distant stars before it traverses the distance to our location ergo we cannot claim conclusive evidence either way.

Originally Posted By: Orac
BTW what was the reasoning behind a nuetron fired at the earths core being faster than light?

(Incidentally, it is only faster than a horizontally emitted beam of light not faster than a beam that is traveling in the same direction.)

When a beam of sub-atomic particles is accelerated horizontally much of the accelerative force is required for no other reason than to overcome the particles' increasing relativistic mass whereas if the beam is projected vertically the planet's gravitational field is aiding the acceleration.

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Originally Posted By: Bill 6

On the assumption that we have already done this dance, my response would most likely have been the same - when the atoms of the medium absorb the photons it is my understanding that the atoms then emit their own photons.

I see nothing there which indicates that the atoms totally absorb some of the photons.

If the increased temperature of the medium is due to a loss of total photons then the emitted light would incur a reduction in intensity.

In order for us to see that the emitted photons are of the same frequency as the original beam we would have to determine the frequency of both beams however the difference between them would be minimal to the point of being virtually indeterminable until we start talking about the considerable number of free atoms of matter scattered over vast tracts of space.

We have no way of determining the frequency of light emitted by distant stars before it traverses the distance to our location ergo we cannot claim conclusive evidence either way.


Again as I said at the time we should be able to do this in the lab which we don't see. I would do it tomorrow if it were true Bill 6 ... nobel prize awaits me if I could prove it true.

Alas as much as you want it to be true to make some observation on cosmology work for you it is not so.

Now your never going to believe me because when we did this dance last time you then went to some sort of science conspiracy theory.

All I can say is I personally don't care if it is true or not, I have no vested interest either way. Unfortunately if I test it comes out false.


Originally Posted By: Bill 6

(Incidentally, it is only faster than a horizontally emitted beam of light not faster than a beam that is traveling in the same direction.)

When a beam of sub-atomic particles is accelerated horizontally much of the accelerative force is required for no other reason than to overcome the particles' increasing relativistic mass whereas if the beam is projected vertically the planet's gravitational field is aiding the acceleration.


Okay I can see the logic behind that so you are extending normal Newtonial principles.

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Originally Posted By: Orac
when we did this dance last time you then went to some sort of science conspiracy theory.

And even a vague reference to same suffices to ridicule a person's submissions.

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Originally Posted By: Bill 6
And even a vague reference to same suffices to ridicule a person's submissions.


There was no riducle intended it was more a statement of what happened.

If you have a claim of some experiment you feel will show something important I am offering to help make it happen if it is within my power.

Certainly therefore to claim that science is conspiring is a falacy we love controversy, well I do personally perhaps there is such thing as establishment although most I know love when we get something we can't explain.


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As a stroke of luck I happened to be reading background for something entirely different on Lubos's website and notice what he posted.

The rumour mill has it the results from those pesky Nuetrinos second run are in and to be released within 2 days ... and even at 2ns spacing between batches they are superluminal on the current testing.

http://motls.blogspot.com/2011/11/opera-neutrinos-ftl-even-at-3-ns.html?

This one is going to get some head scratching from scientists ... break out the popcorn, barbeque and sausages ... physics for the next few weeks is going to get interesting.


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Well, that certainly makes things more interesting. I still have my doubts about it, but I don't have the skills to actually critique their results. Of course the final decision on whether they are traveling faster than light will wait for somebody else to come up with the same thing using a different experiment. In the mean time a lot of people will be running around trying to explain it away, or come up with some kind of theory to match it.

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"those pesky Nuetrinos" made it onto the 6pm (GMT) news on Classic FM, today. I guess they are escaping from the realms of science.


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I checked "Starts With a Bang" just now and Ethan has a link to this site About superluminal neutrinos. This writer has another take on the subject. I haven't followed all of his links yet, so I don't know for sure what he is going on about. He seems to think that it has been established that the neutrinos may be making a very short run at very large superluminal velocities, then slowing to a more natural speed. I really need to check his links to see if I can make head or tales of it. Maybe tomorrow.

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I am quite familar with Sascha's view about pion's before they decay to nuetrinos. There are a few threads of support here and there but what is playing out loudly in my head is the original minos report of FTL nuetrinos.

The suggestion myself and a quite a few others have been suggesting is to lower the energy of the nuetrinos to as low as they can take them.

If the speed remains unchanged then the effect is clearly either a system error or something akin to what Sascha is suggesting.

If the speed is occuring through the nuetrino travel time the nuetrinos should slow down and move closer to the speed of light.

I keep seeing the graph by Tamburini and Laveder which simply plotted the data with no theoretical explaination.



Time to try plotting some new points are what most are saying.


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Ok, I went over and read through Sascha's stuff. I can't say that I really understand what he is talking about, but I sort of followed his discussion based on the neutrinos "splashing" out of our brane into the bulk. The first thing that comes to my mind is that he assumes that the neutrinos all splash out. I don't see that myself. He compares it to an ocean wave that causes drops of water to splash out into the air, where they can travel faster than they could in the water. But I don't see how all of the neutrinos would splash out. I would think that some might, but not all of them, so that what would happen would be that the pulse would smear out, instead of just shortening the transit time.

He did say that he thinks it is probably just some sort of system error, but this is a possible mechanism to explain it if it isn't.

In the mean time we will have to keep on waiting to see if there are other experiments that will confirm the superluminal effect.

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If the superluminal effect is confirmed, will these neutrinos be travelling backwards through time? If not, why not? If so, how can we observe them?


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I think the backwards in time thing is associated with tachyons, which are inherently superluminal. The solution posited by Sascha is a different matter. I'm not sure how much you know about string theory (or as I like to think of it string hypothesis), but there is an extension of string theory to what they call branes. These are multidimensional membranes that exist in a higher dimensional space, the bulk. According to this idea our universe exists in a 3-dimensional (plus time) brane, and we are stuck in this brane. One of Sascha's proposals is that the neutrinos may momentarily burst out of the brane into the bulk. The speed of light is higher in the bulk, so when they fall back into the brane they are further along than they would have been if they had stayed in the brane. He also has some other ways of doing the same thing but I didn't follow up on other things he might have listed.

Keep in mind that the string hypothesis is, as far as I am concerned, still just that. After working on it for over 30 years the string community still hasn't come up with a way to attach it to our universe, and they have no testable predictions. That is why I consider it a hypothesis rather than a theory.

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Could be I go it wrong, but I thought that travelling backwards through time was something that went with FTL travel. Why might it apply to one thing, but not another?

The idea that the neutrinos might pop out of the brane for a moment does seem to require accepting quite a lot on faith. However, I shall have a look at Sascha's ideas.


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Originally Posted By: Bill S.
Could be I go it wrong, but I thought that travelling backwards through time was something that went with FTL travel. Why might it apply to one thing, but not another?

The difference is that the neutrinos would still be traveling at or below light speed in the bulk, it is just that light speed in the bulk is much higher than light speed in the brane. So when they dropped back into the brane they would appear, to us, to have been traveling FTL.

Of course the whole idea of branes is speculative at present. You have to accept a lot of ideas that have not been shown to have anything to do with the real universe.

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Originally Posted By: Johnnes Koelman
Will the ultimate trading package be available soon? If the neutrinos traveled at superluminal speeds, they must have arrived younger than when they were send away. Encoding current foreign exchange rates in superluminal neutrino packets would allow you to get access to future exchange rates. The ultimate trader's dream come tru?


Looks like someone, much better qualified than I, thinks the reversed time bit could be a problem.


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First of course are the obligatory ifs: If the results are upheld, and if the reason the neutrinos are getting there too soon is because they are jumping into the bulk, then:

I can think of no particular reason why there should be any time reversal during the passage of the neutrinos through the bulk. This is not the same thing as the proposed tachyon. The tachyon always travels faster than the speed of light. A particle traveling in the bulk would have no reason to travel faster than the speed of light. It is just that things, including light, travel faster in the bulk than they do in the brane. When the neutrinos jump into the bulk they would sped up, but not turn back in time. The light cone would presumably be pretty much the same. It might have a different slope, but I'm not enough of a physicist to be able to say much about that. Anyway after the neutrinos had traveled a short distance in the bulk something (gravity?) would pull them back into the brane, and they would just wind up have taken a sort of a short cut from the place they started to the place they ended up. You know, like getting off of the city streets and onto the freeway for a little way. If there isn't a back up on the freeway you may make better time than if you stopped at all the lights on the city street.

Now then, excluding the travel through the bulk situation. The idea of sending information back in time does run into the standard time travel paradox. The information would cause changes that would make the information false. Plus of course if they traveled back in time there would be a transfer of energy back in time. If that happened then it seems to me there would be a problem with the basics of QM. The uncertainty principle allows a certain amount of variation in the energy balance of the universe. I suppose that could allow very short time travel events, but I doubt if they could amount to as much as the 60 nS reported. 60 nS isn't much time, but compared to typical high energy reactions it is an enormous time. 60 nS is a long time compared to Planck time.

Bill Gill


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Bill, the first part of your explanation makes perfect sense, as long as you accept another "if": if string theory is correct.

As far as the second part is concerned; if the neutrinos are just taking a short cut, there would be no paradox; just the chance of a quicker way to share information, which would confer an advantage only until everyone could do it.


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Well, in the quote you gave they specifically said that "they must have arrived younger than when they were send away". That certainly tells me that they were talking about traveling back in time. So they would be hit with the time travel paradox. And for that matter, even in that case the advantage would only exist as long as nobody else could do it.

Bill Gill


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In the end, I guess, it all comes down to interpretation.


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A few jumped the gun there were actually two errors they found with the fibre optic cable connection of the GPS to the atomic clock.

One underestimates and the other overestimates and it's not easy to work out what the exact experimental change will be, no change at all is still within the possible outcomes as is removing the 60 ns error.

They are saying they won't actually know till they retest it and see if the changes to the atomic clock timing makes a difference.

Most are guessing since we have a system error the nuetrinos will behave but there is no guarantee :-)
.


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Originally Posted By: Orac

Most are guessing since we have a system error the nuetrinos will behave but there is no guarantee :-)
.


Good point.

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Any idea when a retest is planned?


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Bill, looking back through this thread I found your comments about light travelling faster “in the bulk”, and therefore the neutrinos, if they escaped into the bulk, not travelling FTL. This stirred past thoughts about gravitational lensing. Such thoughts are probably a bit off topic in this thread, so I’m going to start another.


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