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Is there a quanta of rest mass? say multiples of electron mass?

  1. Sep 9, 2006 #1
    do particles of the standard model have rest mass that is quantized, and comes in quantas of mass, with i imagine the electron being the lowest that have rest mass (the neutrino does not appearl to have a rest mass)


    please move to other more appropriate forum
  2. jcsd
  3. Sep 9, 2006 #2


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    You're behind the times. Not only does the neutrino have a small mass, but it participates in one observed and one hypothetical exchange with regard to its mass.

    First the observed one: you know there are really three "flavors" of neutrino, one each associated with the electron, the muon, and the tauon, the three flavors of charged lepton. And these three can actually oscillate, their wave functions turning from one into another. They couldn't do this if they were massless, so the discovery that they do (first hypothesized to explain the "solar neutrino deficit" found by the old neutrino detector in the Homestake Gold mine, and then confirmed at Super Kamiokande in Japan and at other detectors), is the reason they are now believed to have mass.

    And then the hypothetical one. It is needed to explain why the neutrinos have such a small mass, so small it was taken to be zero until the oscillation forced the issue. The proposed answer is the "seesaw mechanism": Suppose that at the pure high energy level where all the quiddities of the standard model smooth out, there are both right and left handed neutrinos, and that they come in pairs, one of each handedness per pair. And they would have zero mass at this high energy level. But as the energy fell, this symmetry would be broken; Only one handedness would be observed (left-) and mass would be acquired. Now the math says the mass would come in by pair, to be shared between the members; but as it plays out not shared equally. The nonobserved right handed neutrino would get the lion's share with only a shred of mass left over for the observed left handed neutrino.

    As to your main question, there's no evidence for it as far as I know. The electron is the lightest particle except the neutrinos, but the quarks are not some even multiple of electron mass as their charge is (1/3) of electron charge. Note however the thread "All the Lepton Masses" on the high energy forum; there are strong formulas relating the masses of different particles. Currently there is no accepted explanation of these formulas, and many physicists dismiss themm as "mere numerology".
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