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Look for neutrinos coming from black holes

Answers the question of whether they can travel faster than light
  [vote for,

If a neutrino can travel faster than the speed of light, neutrinos should be detectable coming from just INSIDE the event horizon of black holes.*

*It may be necessary to throw a neutrino emitter into a large black hole to accomplish this

Voice, Dec 15 2011


       While the practical application of this is at least as far away as sufficiently sensitive instruments to confirm or deny it in other ways, there doesn't seem to be anything theoretically wrong with this idea. [+]
MechE, Dec 15 2011

       I went to the trouble of reading the report that all the fuss is about; it is really interesting stuff, but its authors do not claim that neutrinos can travel faster than light. They obtained some interesting timing results, but unlike the news reports (which contain misinformation that a high school science student should be able to spot) do not draw any particular conclusions.   

       And if neutrinos travel faster than light-in-a-vacuum, wouldn't that redefine the event horizon as being a tiny bit smaller than previously thought?
spidermother, Dec 15 2011

       Would travelling at faster than light mean that neutrinos can escape a gravitational field greater than that which light can escape?   

       One way of looking at the event horizon is that it's a region of spacetime which is warped so much it closes on itself. From that perspective, would travelling any faster enable a particle to escape? Wouldn't it be a bit like the M25 - you can go around slower or faster, but you never actually escape?
MaxwellBuchanan, Dec 15 2011

       [MB] FTL particles couldn't escape from the singularity, which is the point where space goes wonky.   

       All the event horizon is is the point where light can't escape. Even if that is defined by the curvature of space, something moving FTL would break free.
MechE, Dec 15 2011

       As [Voice] alluded to, is there something just inside the event horizon that could emit neutrinos? Possibly a particle/anti-particle thing like the one that produces Hawking radiation?
As the neutrino would have a mass (real or virtual) (or is that momentum?) less than a photon, the force on it due to the gravity of the black hole would be less, so maybe it could escape?
neutrinos_shadow, Dec 15 2011

       // but unlike the news reports (which contain misinformation that a high school science student should be able to spot) //   

       They were worse than that; even I spotted the bullshit, and I barely understand a goddamn thing about this stuff, no matter how much I want to.
Alterother, Dec 16 2011

       Reliable news sources reported it as "unusual data that, if accurate and not due to experimental error or misunderstanding, would seem to indicate neutrinos traveling faster than light". Unreliable news sources picked up the last five words and ran with it.
MechE, Dec 16 2011

       Perhaps a neutrino were just passing by instead of being emitted by something inside the event horizon?
RayfordSteele, Dec 16 2011

       Detecting neutrinos?   

       Do me a favor--turn your thumbnail so the sun would be shining on it, if you could see the sun from where you are. Look at it for a second.   

       Did you see the neutrino? The missing neutrino, I mean.   

       About 65 billion neutrinos passed through your thumbnail in that second. If the earth was between you and the sun, there was maybe one missing.   

       Good luck with a detector.
baconbrain, Dec 17 2011

       Detecting neutrinos is difficult, but it's not impossible to detect a reasonable number with the proper equipment.   

       Of course that's part of the reason why the results are so questionable in the first place, there's a bit of statistical guess work going on.
MechE, Dec 17 2011

       I wonder if it is possible to measure, even if is true.   

       The only reason they could measure the CERN neutrinos, is because they were expecting a spike in activity (detection). Admittedly the signal arrived a little earlier than expected, but still...   

       Dropping something into a 'black hole' necessarilly means you lose all information pertaining to that "thing". The 'black hole' conserves this loss of entropy by emitting a rather random Hawking radiation. Would it be possible to determine a signal from another signal, in this instance. Methinks not!
4whom, Dec 19 2011

       //Dropping something into a 'black hole' necessarilly means you lose all information//   

       This isn't the case. The reason you lose information is because nothing can escape it. The point at which the fastest known thing (light) can't escape is the event horizon. If something can move faster than light, it can escape from a slightly closer point, which is the entire point of this idea. If they are FTL, you won't recapture neutrions sent past the new event horizon, but you will re-capture neutrinos sent from just outside of it, but inside the light event horizon.
MechE, Dec 19 2011

       I am familiar with the concept that the diameter of the event horizon for FTL particles is less than that of the photonic event horizon. My point, however, still stands.   

       The events which produced the 'so-called' FTL neutrinos were STL events. It is this, and only this, that enables us to observe or detect the "FTL neutrinos". By losing the information about the point of time of creation of the FTL, or otherwise, neutrinos, we lose a reference point.
4whom, Dec 19 2011

       I imagine something opposite is happening with the CERN detections. We have a good idea of the creation frame of reference, and not a very good idea of the detection frame of reference.
4whom, Dec 19 2011

       The point is that we wouldn't lose that information. Information loss only occurs at the point of capture and inwards, if the neutrinos are never captrured, information isn't lost.
MechE, Dec 19 2011


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