One more thing. If it is true that the speed of light is not (quite) the absolute speed limit in relativity, neutrinos going faster than light would not break causality (if I understand correctly).
Light barrier broken
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That's really great news and plausible theory as well.I haven't heard about the "speed of space" until now.
The absolute speed limit will probably be the speed of neutrinos because it is closer to the speed of space which is the absolute value...am I correct?
Sep 23, 2011
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#5
That's my (non-specialist) view. The term "speed of space" is unfamiliar because I had to invent it, because everyone has always assumed the constant in relativity was the speed of light. I know enough to know relativity makes sense even if the speed is not the speed of light (it's really just a geometrical theory of space time including a constant which relates space and time).
Very relevant is that there is a lot of experimental evidence constraining the mass of the photon. The strongest constraint seems to be that it is less than 3×10−27 eV/c2 . This is very small indeed. Contrast this with the fact that there is evidence that at least one neutrino has a mass of at least 0.04 eV/c2. But CERN's experiment only used muon neutrinos [CORRECTED], and these
could be lighter . And also if they have a lot of kinetic energy, they
could go very close to the "speed of space".
Oh, one important consequence of a photon with mass would be that the speed of light is dependent on frequency. Radio waves would move slower than light which would be slower than gamma rays. I am pretty sure there is no evidence of any difference before.
I think the speed of neutrinos might also not be the the absolute limit, just closer to it than that of light.
It is also possible that there is something more mysterious that I don't understand that means that all light moves at the same speed despite photons having a small mass. This might be to do with the higher dimensions that have been mentioned.
Looks like a logical theory...and I like it.
Sep 23, 2011
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#7
Ah, maybe not. Sorry to let you down (before the experimenters themselves do at some time) but I have just realised that there is strong evidence that this result is not what it appears. Actually this is probably good news, as there may have been no way to make sense of photons having a mass.
You recall the naked eye supernova SN1987a? One important piece of empirical data from this was that there was a burst of neutrino detection 3 hours before the initial sudden increase in visible light. You might say this too was evidence of neutrinos travelling faster than light, but sadly it was not. The reason is that the neutrino burst is emitted unimpeded by matter from the core, while the supernova explosion itself emits light that has to get through the whole of the star (which apparently took 3 hours). Also this supernova was about 168,000 light years away, so 3 hours was only 1 part in 490 million of the transit time. Even without a reason why the light was slightly delayed, this is spectacularly good agreement between the speeds.
Hence neutrinos travel at a very, very similar speed to light, at least the neutrinos and light that came from SN1987a do.
Sep 23, 2011
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#9
As far as I understand, it will take about a year to get to the stage where they can say either they have discovered the Higgs, or that they have enough evidence to show that the sort of Higgs they are looking for does not exist. It appears although there was a hint they might be near discovery in July, more recent data has hinted that it may not exist.
Oct 14, 2011
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#10
Up to now the view has been neutrinos, like all matter, experiences slowed time when it moves fast. And neutrinos always have kinetic energy that is very high compared to their mass, which should mean speeds close to the speed of light.
However, if it does turn out they move faster than the speed of light through moving in higher dimensions, I am not entirely sure what happens to it. I would assume the mass factor would still be the same as the time dilation factor (mass is increased the same amount as time is slowed and the same amount by which space gets made smaller in special relativity).
But in any case, all normal matter will experience special relativity exactly as before. That it does has been well tested in many experiments (mostly with time dilation).
As for the person travelling in that neutrino, they would need to be rather small. 
I think no non-neutrino matter could travel with the neutrino, since everything else is bound by the speed of light (and is limited to the usual 4 dimensions).
Oct 14, 2011
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#11
lol - I'll pretend you are being serious.
Unfortunately the neutrino has no volume, so there is nowhere to put anything. And quantum theory does not allow you to chop holes in elementary particles. You either get a whole one or none at all.
Nov 19, 2011
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#13
Those speedy little neutrinos won't lie down. Second paper published with improved experimental runs, and no suggestion of any errors in the first results.
Feb 22, 2012
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#14
Finally, it's been laid to rest. Most people were right, and it was an experimental error. Einstein rules!
http://news.sciencemag.org/scienceinsider/2012/02/breaking-news-error-undoes-faster.html?ref=hp
[By the way, it really annoys me when someone participates in a discussion, gets their account deleted, and all their posts are deleted. It leaves one side of a conversation, like the above]
In some open forum discussions, I've found the missing conversations in public internet caches. But unforuntately, that doesn't work as well in these sorts of groups. Information was lost. (Not sure if that works in favor of or against the idea in Hawkins latest research about black holes.)
Your sarcasm is cutting me, Elroch! I really need to land a job soon Lol.
I thought so. I wish there was a way to stop new pharmacy schools from opening up. They are mass producing pharmacy students that are loaded up on student loans from jacked up tuition, and sending them off into an already flooded pharmacy market with false promises. It is not good for them and not good for me. I never thought it would be this tough for a licensed pharmacist to obtain a job.
Timotheus drew my attention to what could be some huge physics news today. CERN report having measured the speed of neutrinos as being slightly faster than that of light.
My first thought was that surely there must be some mistake, and I think this is still a hypothesis at CERN. But then I saw an alternative explanation which may be more interesting.
We think of the speed of light as being fundamental, this being closely tied to the fact that photons are massless. But in relativity, it is really what might be called the "speed of space" that is constant, and constrains the speed at which everything else can travel, light being one of those things. One argument for photons moving at the speed of space is really that they have to in order to have any energy, as they are massless (are there experiments that actually show the speed of light is the "speed of space" in relativity?)
Meanwhile, previous work has inferred that neutrinos must have small masses (well, at least some of them, but probably all of them). In a sense, light passes through space with the greatest of ease, with no mass being generated by Higgs bosons, whereas neutrinos are slightly hindered by virtual Higgs and acquire some mass.
But what if neutrinos actually pass through space more easily than light? We know that neutrinos interact with matter a lot more weakly than light and don't interact with light at all, so surely they interact less with virtual particles of similar types. Can photons acquire a tiny amount of mass because of their interactions with virtual particles?
This is so fascinating, when the Higgs is confirmed next year, it may only make page 2.