Tachyonic neutrinos can explain SN 1987A neutrinos beating photons to Earth, and tachyonic neutrinos can explain the CERN observations, but, critically, they cannot explain both phenomena simultaneously. The SN 1987A neutrinos apparently moved slower than the CERN neutrinos, when the pure tachyonic explanation would have them move faster than the CERN neutrinos.
This isn’t to say neutrinos couldn’t be tachyons, but it would still leave the CERN data requiring an explanation.
Your point is correct. But I’d also like to note that in case anyone thinks that SN 1987A is a problem for physics- the conventional model explains SN 1987A neutrinos beating the photos to Earth. Neutrinos are produced in the core of a star when it goes supernova. Light has to slowly works its way out from the core going through all the matter, or is produced at the very upper stages of the star. Neutrinos don’t interact with much matter so they get to go through quickly and so get a few hours head start. Since they are traveling very close to the speed of light they can arrive before the light.
This is the conventional explanation. If neutrinos routinely traveled faster than light, we’d expect the SN 1987A neutrinos to have arrived even earlier than the three hours they arrived before the light. In particular, if they traveled as fast as CERN predicted then they should have arrived about 3-5 year before the photons. Now, we didn’t have good neutrino detectors much before 1987 so it is possible that there was a burst we missed in that time range. But if so, why was there a separate pack of much slower neutrinos that arrived when we expected?
There may be possible explanations for this that fit both data . It is remotely possible for example that the tauon and muon neutrinos are tachyons but the electron neutrino is not, or that all but the electron neutrino are tachyons. If one then monkeyed with the oscillation parameters it might be possible to get that the CERN sort of beam would arrive fast but the beam from SN 1987A would arrive at the right time. I haven’t worked the numbers out, but my understanding is that we have not awful estimates for the oscillation behavior which should prevent this kiudge from working. It might work if one had another type of neutrino since that would give you six more parameters to play with. Other experiments can upper bound the number of neutrino types with a high probability, and the standard estimates say that there probably aren’t more than 6 neutrino types. So there is room here.
I don’t know enough about the underlying physics to evaluate how plausible this sort of thing is. Right now it seems that a lot of people are brainstorming different ideas.
This is from a naive, back of the envelope calculation without taking differing energies into account. One thing to note that by some estimates tachyons should slow down as they get more energy. If that’s the case then the discrepancy may make sense since the neutrinos from the supernova should be I think higher energy.
Tachyonic neutrinos can explain SN 1987A neutrinos beating photons to Earth, and tachyonic neutrinos can explain the CERN observations, but, critically, they cannot explain both phenomena simultaneously. The SN 1987A neutrinos apparently moved slower than the CERN neutrinos, when the pure tachyonic explanation would have them move faster than the CERN neutrinos.
This isn’t to say neutrinos couldn’t be tachyons, but it would still leave the CERN data requiring an explanation.
Your point is correct. But I’d also like to note that in case anyone thinks that SN 1987A is a problem for physics- the conventional model explains SN 1987A neutrinos beating the photos to Earth. Neutrinos are produced in the core of a star when it goes supernova. Light has to slowly works its way out from the core going through all the matter, or is produced at the very upper stages of the star. Neutrinos don’t interact with much matter so they get to go through quickly and so get a few hours head start. Since they are traveling very close to the speed of light they can arrive before the light.
This is the conventional explanation. If neutrinos routinely traveled faster than light, we’d expect the SN 1987A neutrinos to have arrived even earlier than the three hours they arrived before the light. In particular, if they traveled as fast as CERN predicted then they should have arrived about 3-5 year before the photons. Now, we didn’t have good neutrino detectors much before 1987 so it is possible that there was a burst we missed in that time range. But if so, why was there a separate pack of much slower neutrinos that arrived when we expected?
There may be possible explanations for this that fit both data . It is remotely possible for example that the tauon and muon neutrinos are tachyons but the electron neutrino is not, or that all but the electron neutrino are tachyons. If one then monkeyed with the oscillation parameters it might be possible to get that the CERN sort of beam would arrive fast but the beam from SN 1987A would arrive at the right time. I haven’t worked the numbers out, but my understanding is that we have not awful estimates for the oscillation behavior which should prevent this kiudge from working. It might work if one had another type of neutrino since that would give you six more parameters to play with. Other experiments can upper bound the number of neutrino types with a high probability, and the standard estimates say that there probably aren’t more than 6 neutrino types. So there is room here.
I don’t know enough about the underlying physics to evaluate how plausible this sort of thing is. Right now it seems that a lot of people are brainstorming different ideas.
Is this just assuming that they travel at the same speed as recorded for the CERN ones, or has any adjustment been made for their differing energies?
This is from a naive, back of the envelope calculation without taking differing energies into account. One thing to note that by some estimates tachyons should slow down as they get more energy. If that’s the case then the discrepancy may make sense since the neutrinos from the supernova should be I think higher energy.
Nope. As I said here the ones at CERN are 17GeV, whereas the ones from the supernova were 6.7MeV.
Ok. In that case this hypothesis seriously fails.