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New Paper Claims Neutrino Is Likely a Faster-Than-Light Particle
HughPickens.com writes Phys.org reports that in a new paper accepted by the journal Astroparticle Physics, Robert Ehrlich, a recently retired physicist from George Mason University, claims that the neutrino is very likely a tachyon or faster-than-light particle. Ehrlich's new claim of faster-than-light neutrinos is based on a much more sensitive method than measuring their speed, namely by finding their mass. The result relies on tachyons having an imaginary mass, or a negative mass squared. Imaginary mass particles have the weird property that they speed up as they lose energy – the value of their imaginary mass being defined by the rate at which this occurs. According to Ehrlich, the magnitude of the neutrino's imaginary mass is 0.33 electronvolts, or 2/3 of a millionth that of an electron. He deduces this value by showing that six different observations from cosmic rays, cosmology, and particle physics all yield this same value within their margin of error. One check on Ehrlich's claim could come from the experiment known as KATRIN, which should start taking data in 2015. In this experiment the mass of the neutrino could be revealed by looking at the shape of the spectrum in the beta decay of tritium, the heaviest isotope of hydrogen.
But be careful. There have been many such claims, the last being in 2011 when the "OPERA" experiment measured the speed of neutrinos and claimed they travelled a tiny amount faster than light. When their speed was measured again the original result was found to be in error – the result of a loose cable no less. "Before you try designing a "tachyon telephone" to send messages back in time to your earlier self it might be prudent to see if Ehrlich's claim is corroborated by others."
But be careful. There have been many such claims, the last being in 2011 when the "OPERA" experiment measured the speed of neutrinos and claimed they travelled a tiny amount faster than light. When their speed was measured again the original result was found to be in error – the result of a loose cable no less. "Before you try designing a "tachyon telephone" to send messages back in time to your earlier self it might be prudent to see if Ehrlich's claim is corroborated by others."
Nor did the Opera team claim any such thing, they observed faster than light tachyons, couldn't find why they had got those results and contacted another team to ensure their equipment was faulty. People in those positions don't just make wild speculations with corroborated evidence.
Imaginary isn't "negative mass squared"
The sentence is slightly ambiguous, however;
The result relies on tachyons having ... a negative (mass squared)
09F91102 no, 455FE104 nope, F190A1E8 uh-uh, 7A5F8A09 that's not it, C87294CE no. Ah! 452F6E403CDF10714E41DFAA257D313F.
Any positive mass, you mean. Imaginary numbers aren't positive.
drdread66 doesn't have it backwards, the original article is unclear in its phrasing. It should have stated that the square of the mass is negative, which can be assumed when it accurately states that the mass is an imaginary number. Another commenter has linked back to the original paper on archiv.org; I always recommend going back to the source for science reporting anywhere online. As Einstein said when asked about his thoughts on a one page summary of the theory of relativity from a local paper, "things should be made as simple as possible, but not simpler."
- W. Blaine Dowler
http://www.bureau42.com
In that supernova (the first observed in 1987 hence the name), the supernova was close enough that we were actually able to detect the neutrinos from it. The neutrinos arrived about three hours before the light from the supernova. But that's not evidence for faster than light neutrinos, since one actually expects this to happen. In the standard way of viewing things, the neutrinos move very very close to the speed of light, but during a core-collapse supernova like SN 1987A, the neutrinos are produced in the core at the beginning of the process. They then flee the star without interacting with the matter, whereas the light produced in the core is slowed down by all the matter in the way, so the neutrinos get a few hours head start.
The problem for FTL neutrinos is that if the neutrions were even a tiny bit faster than the speed of light they should have arrived much much earlier. This is strong evidence against FTL neutrinos. In the paper in question, he mentions SN 1987A in the context of testing his hypothesis in an alternate way using a supernova and the exact distribution of the neutrinos from one but doesn't discuss anywhere I can see the more basic issue of the neutrinos arriving at close to the same time as the light.
Saying "has a negative mass squared" can be misinterpreted more easily than "the square of the mass is negative." One person read it as intended, and another read it as "you take a negative mass and square it." If the wording was completely clear, that misinterpretation couldn't have happened. Different brains will associate the words "negative mass" as a complete unit while others will associate "mass squared" as a complete unit.
- W. Blaine Dowler
http://www.bureau42.com
Did any of you who moderated parent up actually look at the link posted? It's a personal website defending his pet crackpot theory of everything.