Ulukai on 22/9/2011 at 19:20
"They" being scientists at CERN and well, (
http://www.reuters.com/article/2011/09/22/us-science-light-idUSTRE78L4FH20110922) maybe, and well, some particles may have done.
"If confirmed, the discovery would overturn a key part of Albert Einstein's 1905 theory of special relativity, which says that nothing in the universe can travel faster than light." That article is very short on facts but hey, exciting times if it is confirmed. I remain skeptical, although this is CERN and not some random crackpot claiming to have invented another perpetual motion machine.
Kuuso on 22/9/2011 at 19:37
Well, it was bound to happen sometime I guess. I think quantum physics has gone so far that grand older theories are bound to crack up at some point. Now we just need the Japs or americans to confirm this.
demagogue on 22/9/2011 at 19:39
I just finished reading "The Theory of Almost Everything" on the Standard Model, so I'm already on a sort of high on this stuff. But I read that going over the speed of light was never conceptually disqualified, it was just the given speed of massless particles so it'd take a special kind of particle or situation to do it. Anyway, be very interesting to see what they make out of it if it's verified. New physics!
PeeperStorm on 22/9/2011 at 20:43
Scientists have known for a long time that the speed of light varies depending on circumstances, such as the medium that the light is traveling in. Nothing worth talking about here until an assload of additional testing has been done, especially since the difference is such a small fraction of c.
heywood on 22/9/2011 at 20:57
These are neutrinos, which have mass. And there is no quantum entanglement involved. So if the result holds up, it busts relativity and causality.
There have been experiments before suggesting neutrinos could be superluminal, but nothing conclusive.
There's a seminar at CERN later today where the work will be presented. Link to webcast here in case anybody is inclined:
(
http://indico.cern.ch/conferenceDisplay.py?confId=155620) http://indico.cern.ch/conferenceDisplay.py?confId=155620
Muzman on 22/9/2011 at 21:23
Quote:
They've only gone and broken the speed of light haven't they
This is why we can't have nice things.
Sulphur on 22/9/2011 at 22:17
Well, Einstein's formulae still hold up because relativity's predictions were always accurate until now; it's just likely corollaries and additions need to be made to account for what's happening with neutrinos, which are a strange if important bunch of particles - it's all rather exciting, though.
Mingan on 22/9/2011 at 23:36
I fail to understand how 'breaking' c breaks causality, because as far as i know those neutrinos took some time to get to the detector, only just slightly faster than expected. Am I going dumb?
Pyrian on 23/9/2011 at 02:57
C is often referred to as the speed of light, or more properly as the speed of light in a vacuum, but it's significance is that it's the speed of causality. Massless particles like photons travel the very lip of causality, which means that no time actually passes for the particle between its emission and its absorption (light in a medium is slowed because it effects, and is affected by, that medium). A tachyon - a particle moving faster than c - should have negative mass and its own causality should be moving backwards in time.
...Interestingly, I'm pretty sure the results that indicated that neutrinos have mass are more properly indications that its mass cannot be zero. I don't think they rule out negative numbers. :D (A massless particle travels at c, the leading edge of causality, and therefore time does not pass for that particle; neutrinos oscillate states in transit, so cannot be travelling at exactly c, so cannot have zero mass.)
Theoretically, if this result holds up, and if you could write a message on a neutrino and read it off of it, you would be able to read a message at its origin that was written at its destination.
