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#41658 11/29/11 06:19 AM
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The sub-atomic particle neutrino travels faster than light. If this is true, Einstein's SR is definitely wronged and all equations deduced from it, length contraction, time dilation, Rest Mass and The famous formula E=mc^2 wronged.

Since I study SR, I think we should not set the speed to c. If we not set this limit, and change c to infinity, Galilean's mechanics is actually right! x'=x-vt and t'=t

And I am curious on the speed of our thought. Light travels from it source to our eyes. Our eyes receptors turn it to nerve impulses and detected by our brains. If our brain is not fast enough, we can't see things continuously and smoothly. If we turn around, we can't even see any image if thoughts are not fast enough . I actually think that thoughts travel faster than light. Many many times faster than light if we fully utilized our brain.

.
gan #41659 11/29/11 09:51 AM
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Gan you are the young science genius you should know better.

Lets discuss the facts:

-> We have one experiment in which we appear to have superluminal nuetrinos there is a massive possibility that the result is nothing more than an experiment error we need confirmation first before we take it seriously.

-> Next it was a particle that was found going faster than the speed of light so it may have no implication for SR/GR. Remember QM effects have long been known to transfer faster than light (Einsteins spooky action at distance) we simply say you can't transmit information in the effect.

-> Ok so why may a particle be different. Well we have made light go superluminal in a special media (http://www.nature.com/nature/journal/v406/n6793/abs/406277a0.html) the effect occurs because experimentally it looks like this (http://www.princeton.edu/~adogariu/fast/). Note the nuetrinos are moving through matter not a vacuum so it could simply be telling you nuetrinos see matter as a media.

-> QM places doubts whether particles are even real. There are many unproven theories in QM in which particles are simply phantoms we see from QM forces or the particles may be moving to a different "space" and back. Within the QM realm therefore there are many ways a particles could go superluminal without violating SR/GR. The exact nature of a nuetrino is not in any way precisely known.

Okay so there are the options we have in within current science understandings and there are possibly a few others.

The other option is the theories are all wrong as you suggest and we need a new one.

You have suggested Galilean's mechanics which has been around a long time probably second only to MOND. Perhaps your homework is to read why we don't support Galilean's mechanics, the key is it sort of works at the SR level but try taking it to real world and merging it with QM :-)

You will find the background here (http://en.wikipedia.org/wiki/Galilean_invariance)

The key point at bottom

Quote:

Albert Einstein's central insight in formulating special relativity was that, for full consistency with electromagnetism, mechanics must also be revised such that Lorentz invariance replaces Galilean invariance. At the low relative velocities characteristic of everyday life, Lorentz invariance and Galilean invariance are nearly the same, but for relative velocities close to that of light they are very different.


We can trivially disprove the theory in the electromagnetic realm ... the LHC itself is proof of that Galilean's mechanics is wrong ... read up on how they circulate the particles around the LHC :-)

Last edited by Orac; 11/29/11 02:00 PM.

I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.
gan #41667 11/29/11 03:24 PM
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One very naïve question: Do we have sound experimental evidence for neutrinos travelling at subluminal speed?


There never was nothing.
Bill S. #41669 11/29/11 03:52 PM
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To my knowledge no but I will do a more exhaustive check after hours. I suspect that is because we assumed nuetrinos don't ever see anything as a "media" including matter and that is infact one of the questions I pose above.


I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.
Orac #41670 11/29/11 04:02 PM
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Should add in this here as well ... which is whether the good old sterile nuetrino is real.

http://www.physorg.com/news/2011-11-physicists-fourth-neutrino.html


I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.
Orac #41671 11/29/11 04:50 PM
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I also throw in a reasonable layman site on quantum decoherence (theory that particles are illussions) and there explaination of why you could no sooner actually measure a particle than you could a rainbow

http://www.ipod.org.uk/reality/reality_decoherence.asp

Last edited by Orac; 11/29/11 04:54 PM.

I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.
Bill S. #41673 11/29/11 05:59 PM
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Originally Posted By: Bill S.
One very naïve question: Do we have sound experimental evidence for neutrinos travelling at subluminal speed?

Well, for a long time it was thought that neutrinos possibly, but not necessarily, traveled at light speed. That is that they had a zero rest mass. When they actually started detecting neutrinos they found that they were detecting about 1/3 of the number of neutrinos that they expected from the Sun. This caused all kinds of conjectures as to what was going on. Well, what their detector was catching was one particular type of neutrino, which was the type expected to be generated in the Sun. When they stared detecting other types they found that the number of detections went up to the expected number, but they came in 3 types. That was when they figured out that the neutrinos were oscillating among the 3 types as they traveled from the Sun. But that implies that the neutrino travels as less than light speed, so that they would have time to make the changes. Traveling at light speed the neutrinos internal clocks would be stopped with respect to our clocks and they would not have time to make the oscillations. So then we have pretty good evidence that neutrinos do travel at less than light speed.

Bill Gill


C is not the speed of light in a vacuum.
C is the universal speed limit.
gan #41675 11/29/11 06:13 PM
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Thanks Bill - and you explained that without mentioning a F of R for something travelling at "c". smile


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gan #41676 11/29/11 06:19 PM
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Now I'm really confused!

Doesn't light undergo changes, e.g. redshift, when travelling from A to B?
How can it do this in zero time?
Do the changes occur only in our F of R?
If so, could the same not apply to neutrinos?


There never was nothing.
Bill S. #41679 11/29/11 08:25 PM
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Originally Posted By: Bill S.
Now I'm really confused!

Doesn't light undergo changes, e.g. redshift, when travelling from A to B?
How can it do this in zero time?
Do the changes occur only in our F of R?
If so, could the same not apply to neutrinos?

The red shift is a whole different thing. Actually it is the Doppler shift. The shift is red if something is traveling away from you and blue if it is traveling toward you. Here is Wikipedias explanation. Anyway the Doppler shift has nothing to do with SR.

Bill Gill


C is not the speed of light in a vacuum.
C is the universal speed limit.
Bill #41680 11/30/11 12:50 AM
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Okay let me wade in.

Something travelling at the speed it is relatively easy to calculate the redshift on because the speed "c" is constant. But something travelling at the speed of light also has no mass.

Something >> with mass << travelling relatively slow is also easy to calculate the redshift ... police use it to clock your speeding car.

Something >> with mass << moving very close to the speed of light is very very very hard to calculate redshift on because the object is going relativistic because you would need to factor in the gamma of the relativistic speed (http://scienceworld.wolfram.com/physics/RelativisticGamma.html)

Relic nuetrinos would have the equivalent of the CMB and it is called CNB (Cosmin Nuetrino background) but attempts to probe it have so far failed. The precise mass and speeds of the nuetrino itself are still somewhat in doubt throw in the gamma factor it gets a little challenging.

It is of extreme interest to cosmology because it would be a time after the big bang and wikipedia has a reference which is far from adequate IMO (http://en.wikipedia.org/wiki/Cosmic_neutrino_background)

Last edited by Orac; 11/30/11 12:51 AM.

I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.
gan #41684 11/30/11 05:13 AM
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Ok... Let me show why I think that Galilean Mechanics is right.
Now we follow what Lorentz did but not on photon state. That means we use a particle that are moving very fast. And we don't know its velocity.Let the particle velocity a.

x2+y2+z2=(at)2
x'2+y'2+z'2=(at')2
y=y' z=z'

x2-(at)2=x'2-(at')2
And we solve for x' and t' , it will be same in the Lorentz Transformation except for c is changing to a.

x'=(x-vt)/sqrt(1-v2/a2)
t'=(t-vx/a2)/sqrt(1-v2/a2)
If we set speed of light is the fastest velocity in the whole universe, right, you are making the reality by setting a->c

x'=(x-vt)/sqrt(1-v2/c2)
t'=(t-vx/c2)/sqrt(1-v2/c2)
And this is the Lorentz transformation.

In my transformation, I don't think that no particle can travel faster than light. There must some can travel faster than light. Even though it is not in our universe or dimension. We set a->infinity.
Ok,now let see.

x'=(x-vt)/sqrt(1-v2/a2)
t'=(t-vx/a2)/sqrt(1-v2/a2)
When a->infinity

x'=x-vt
t'=t

Galilean's transformation did wrong in Lorentz when v is very big. But if we change a frame, by setting the whole reality. He is actually right no matter how the v goes...

gan #41688 11/30/11 06:17 AM
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You already hit the snag Gan

>> though it is not in our universe or dimension <<

So you can't see it or measure it smile

You are now in the realm of Bill S's tachyonics.

Now for bonus points for homework at this stage you have ignored what is happening to mass in your consideration so go back and factor in what happens for mass.


I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.
gan #41698 11/30/11 11:41 AM
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Mass? m=m0 if you follow my steps... No such things as E=mc2 in that transformation

gan #41699 11/30/11 01:57 PM
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Edit: I modified this answer I was going to give you the answer but I have thought about it and best to get you to do your maths thing.

Solve for time for a particle going faster than the speed of light for both transforms.

Now solve conservation of energy for both transforms as you take a mass from rest to twice the speed of light.

So we have two totally different results ... we are scientists. Experimentally how can we decide which of these two is right.

Next lets take our two theories out into the field.

A rotating star explodes we see the explosion. If your Galilean transformation is right I am going to see a large range of velocities correct because some of the rotating photons will be going away from me when the star exploded and some coming towards me so I should get c+v <-> c-v spread of photons coming towards me and they are going to arrive over a long period if the star is along way from us? Now read up on the explosion and mesurements of the red and blue shifts arrival times from the Crab Nebula at a distance of 6000 light years.

Finally lets put our two theories to the test. Lets bounce a photon backward and forward on a rotating lab table and compare it to an atomic clock (http://prl.aps.org/abstract/PRL/v103/i9/e090401)

Last edited by Orac; 11/30/11 03:39 PM.

I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.
gan #41703 11/30/11 09:56 PM
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Originally Posted By: Bill
The red shift is a whole different thing. Actually it is the Doppler shift.


I’m reasonably familiar with the Doppler Effect and how it works. In fact, I suspect that the cause of the red shift in the Universe is a slightly different thing. As I understand it the Doppler Effect results from the fact that the source of the waves (originally sound) is moving relative to the medium in which the waves are propagating; thus, stretching or shrinking occurs on leaving the source. Unless we return to the luminiferous ether, such cannot be the case with light. The red shift of light from distant galaxy groups comes about because space is expanding while the light is passing through it. If, according to the photon’s “internal clock” the journey takes no time, when does the red shift occur? Is the red shift real only in the F of R of the observer?


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Bill S. #41707 11/30/11 11:53 PM
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Sorry if I misunderstood you. Yes the astronomical red shift is indeed caused by the stretching of space. But that doesn't matter to the speed of light. The speed of light is the same for any observer at any time or any place. The stretching of space (astronomical red shift[asr]) doesn't cause the speed to change, just the wavelength. Assume the following line represents the wave packet of a photon as it leaves the source at time t0.

----------------

Then at time t1 at a point in space so that the asr is 2.0 (.5?), that is the time interval between the emission and observation is far enough that the distance has doubled. Now the wave packet will look something like this.

- - - - - - - - - - - - - - - - -

Well, I hope that is about the right length. The second wave packet should be twice the first one.

Anyway, the speed doesn't have to change, the wave is just spread over a greater distance.

The best I can say about the internal clock of the photon is that it doesn't matter. The following is a top of the head discussion, and may not be completely right. I hope it will cover the situation adequately.

The photon exists from the time of emission to the time of absorption with no notice of the passage of time. It seems to me that the photon itself doesn't change when it is red shifted. Only our observation of it changes. And if I think any more about it I can see getting myself all wrapped up in words that don't really mean anything. The basic thing about this is that time has no meaning to the photon. It isn't like the neutrinos which can oscillate between the 3 forms if they aren't traveling at the speed of light.

Bill Gill


C is not the speed of light in a vacuum.
C is the universal speed limit.

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