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Cool. What kind of specialty schools?

 

Mostly schools granting non-transferable credit for two-year certifications: Information technology, Medical transcriptionist, Certified nursing assistant, Business and Accounting, that sort of thing.

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Putting this here for Lucius, since it's prose follow-up to something in the haiku thread.

 

There seem to be three flavor eigenstates, or just flavors, of neutrinos: each neutrino is associated with a lepton. Electron neutrinos go with electrons (and anti-electrons, a/k/a positrons). Muon neutrinos go with muons and their antiparticle. Tau neutrinos go with tau leptons. These flavors matter for reactions with other particles. As an example, an isolated neutron is unstable and it will decay into a proton, an electron, and a neutrino. That neutrino is *always* an electron neutrino. There are other reactions that will produce particles including a muon and a neutrino. In such a reaction, that neutrino is *always* a muon neutrino.

 

If messed with, though, one flavor of neutrino can turn into a different flavor. That is, once an electron neutrino is made, somewhere later in its travel if you try catching it, it may no longer be an electron neutrino; it may be a muon neutrino.

 

This can only happen if the neutrinos have a nonzero mass (in the original concept, and for decades thereafter, it was assumed they were massless) and if the masses are modestly different and the actual "real masses" of the neutrinos are not exactly the same as the average massese of the three neutrino flavors. In that case, a neutrino in one of these "mass eigenstates" will be a mixture of more than one of the flavors, and the probability of finding a particular neutrino as a particular flavor varies as the neutrino travels. It oscillates among the flavors.

 

We have seen this in more than one way. The "solar neutrino problem" was the situation that Ray Davis's chlorine-based experiment for detecting neutrinos from the Sun did detect neutrinos, but only about 40% of the predicted number; this problem persisted from the mid-1960s into the 1990s. During that time it was the only means capable of detecting solar neutrinos, but because it involved a reaction that made an electron, it could only detect electron neutrinos. An exhaustive theoretical analysis of the solar interior model showed that every possible adjustment to the solar model made the discrepancy worse. With the development of adequate neutrino detectors in the 1990s, capable of seeing both electron and muon neutrinos, the "flavor oscillation" was seen both in neutrinos made by particle accelerators and in the solar neutrinos. Including the effects of the oscillations turns the chlorine experiment's result into a full success, with the brilliant link to then-unknown physics operating in the neutrinos.

 

Finally, the word "eigenstates" is from mathematics; it refers to the "characteristic vectors" of a matrix of equations (linear algebra). In intermediate physics problems for coupled oscillators, the behavior of the system looks messy if you try describing it in terms of the individual oscillators, but is much easier to understand if expressed in these characteristic vectors, which describe the natural modes of oscillation of the *system*, not the individual pieces of the system.

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Well, this is all quantum mechanical stuff. The goofy-sounding Schrodinger's cat analogy is exactly applicable here; the cat in the box no longer has the "alive" and "dead" flavors as eigenstates. Instead it is best described as in eigenstates which are a time-varying mixture of the alive and dead flavors.

 

Schrodinger initially concocted that analogy as an attempt to illustrate just how ridiculous the whole intellectual construct is, but like Fred Hoyle's intended-to-be-disparaging "Big Bang" label for that cosmology theory, it has been embraced as a valid word picture for the idea.

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