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[Ultimuh]

does duct tape count as a metamaterial yet?

It sure should. 

[Virex]

In a cave, actually.

And all he had was a box of scraps.

This is why you don't dump radioactive waste in a cave. Forget dirty bombs, before you know it some punk comes along and all GPS systems stop working.

[Bohandas]

How much faster than the speed of light were the neutrinos clocked at? If it was just a little bit faster (and the result is shown not to be due to an equipment error), then the most likely tweak that needs to be made to the existing theory is that the recorded value for the speed of light needs to be increased a little. IIRC, somebody else already mentioned (though I can't seem to locate where) that the value typically given for c apparently does not take the refractive index of vacuum energy into account.

[Virex]

Actually, it does. the Scharnhorst effect is what happens if you reduce the refractive index of a vacuum using the Casimir effect. Incidentally, said effect would not break casualty even though the photons go faster than the speed of light. (I'm not qualified to explain that though, Wiki links to some papers on the subject)

[Starver]

Well, my simple explanation[1] is that strictly speaking a breaking of causality requires an effect to pre-empt its own cause[2].  And this has not been observed (or even said to have been thought to have occurred, by the cautious experimenters who sheepishly released the initial news).  All that is seen is something arriving before it should have, but still a positive amount of time (by any practical frame of reference[3]) after it departed.

[1] If, indeed, I ever have a simple explanation.

[2] IMHO, as and where the universe would allow this, it would be a constructive/reinforcing/self-sustaining loop, but that's just my favourite and most aesthetically pleasing version of various time-travel conundrums, in both fact and fiction.

[3] Admittedly a hypothetical light-beam, having departed slightly before the rogue neutrinos, may note on arriving at the same designationedit: 'destination' (sorry, strange thinko, that) that the receiver had responded to something that hadn't happened yet in its own rather particular time-frame, but there's still no loop of information possible purely by that mechanism.  Gee, and I thought I was keeping this explanation simple.  So much for that idea...

[RedWarrior0]

Actually, is there a possibility of a mild warping of space? Suppose that a couple of Planck lengths contracted into one a couple hundred (thousand? Million?) times.

[MonkeyHead]

That just raises the question of what mechanism caused the distortion... each and every single time, and it isnt easily observable.

[Bohandas]

Actually, it does. the Scharnhorst effect is what happens if you reduce the refractive index of a vacuum using the Casimir effect. Incidentally, said effect would not break casualty even though the photons go faster than the speed of light. (I'm not qualified to explain that though, Wiki links to some papers on the subject)

If the Scharnhorst effect is proven wouldn't that just mean that the current recorded value of c is too low? That there was a variable/source of interference (the refractive index of vacuum energy) that previous experiments forgot to account for?

[Virex]

No, because the speed of light as it appears in the laws of nature is the propagation velocity of light in a standard vacuum. If you still believe in relativity, it's the absolute velocity that all observers see as equal. The Scharnhorst effect increases the speed of the photons passing through the plates, but does not alter the other definitions of the speed of light.

[Tilla]

Fuck searching through all the pages, this has probably already been posted but worth it anyway.

[Urist Imiknorris]

I started doing that with doomsday prophecies.

[Bohandas]

I started doing that with doomsday prophecies.

That's an even better idea than the one in the comic. If you lose the bet it COMPLETELY doesn't matter.

I believe it was Joseph Bruce who said "Money ain't shit among the dead"

[Another]

Well bang goes my effort at a nobel prize for finding the 96% of the universe we are missing.

My next best idea is some form of shortcut/tunnelling through those tiny rolled up extra dimensions suggested by string or M theory.

I think that you may be about 13 years late with this: http://arxiv.org/abs/hep-ph/0008032 . That paper also specifically suggested to check for high energy neutrino speed deviations at a Long Baseline Experiment with the LHC.

On a positive note - this year's Nobel prize was awarded for the discovery of an effect commonly called Dark Energy. Explaining the cause of Dark Energy will be certainly worth at least one more.

P.S. I found this article (already mentioned in this thread, thanks Osmosis Jones) to be the best at describing why v>c could lead to backwards time travel. In short backwards time travel requires both relativity to still be true and specific direction signals at v>c to be simultaneously possible in 2 different moving relative to each other reference frames. Causality could be saved by either special relativity not being "true" (your GPS is still working, isn't it?) or by existence of various other additional principles neither of which is conformed or disproved yet. Though a special "absolute" field would probably cause at least some seasonal variation in observed (if the CERN-OPERA data is to be believed) c+7.5 km/s neutrino speed due to +-30 km/s Earth orbital speed. I would really not like Hawking's "chronology protection conjecture" to be the case but it is fully consistent with general quantum mechanics.

Trying to produce a causality paradox with only one frame of reference as some have tried here or with frames of reference that are not strongly relativistically (Lorentz) transformed relative to each other is futile. Newton-Galilean world was inherently causally-safe even with instant signals.

[Il Palazzo]

Did you just mention aether there?

[Another]

I what part? Dark Energy or the possibility that there may exist a field that doesn't transform with Lorentz transformations? The later is IMHO hinted to be less likely the case by this topic neutrino results.

Providing that such a field has zero strong and electroweak couplings (good luck at detecting it) it could exist. That and the quantum foams are quite hot theoretical research topic at the moment. Nothing has a definite supporting experimental evidence now and a lot of the models were actually disproved by cosmological observations. Some potentially disprovable (falsifiable) models still hold.