Light Notes on Opera

Theory papers are popping up already about Opera. This is the first I've read, and they note the same problem with tachyon-type neutrinos I did (the energy dependence of the speed is wrong), and then add a pion decay issue to the mix as well. The Opera "tachyon mass" is too big and the beam energy is wrong for pion decay with these masses, and the amount of energy available for the electron neutrino in muon decay would be so restricted that an effect should have been seen decades ago. (Muon decay is one type of beta decay. Nuclear beta decay has been studied very carefully in an effort to determine the electron neutrino mass.)

They bring up a modification I'd not heard of before: Coleman/Glashow superluminal particles, where every particle has its own mass and its own light-speed. Weird, but not inconsistent with the data--but neutrino oscillations are very hard to account for in that model.

Naturally IceCube collaborators are hard at work trying to figure out what they can do to confirm/disprove the effect. I am not at liberty to describe this.

That might seem a little rude, but there's good reason for keeping quiet.

The first iterations of the discussions involve a lot of brainstorming and the discussions have to be frank. People have to be willing to say things that eventually turn out to be wrong, or not even wrong. If I were to announce their ideas prematurely, they might be deeply embarrassed by a calculation error that was caught after I announced their ideas; and outsiders who rely on the integrity of our results could be mislead into thinking that wild ideas are what we have actually discovered.

If I suppress names, then it looks like I came up with all sorts of wonderful ideas, and that's not quite honest.

So, I'll mention what I think and what other people have published, but I won't talk about the internal discussions.

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Before I posted this, another paper popped up, this one claiming that superluminal neutrinos would brem off electron positron pairs so fast that they'd slow down to low energies long before reaching the Opera targets.

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UPDATE: Halzen pointed out that IceCube/AMANDA already excluded differences in speeds of different masses of neutrinos down to a fraction of E-27 for neutrinos in the 10GeV and higher range. So my guess last week about different neutrinos having different speed limits is probably ruled out. I have to puzzle out the paper and see.