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On fundamental level, rest mass = 0?

  1. Jun 2, 2010 #1
    Is rest mass just an illusion?

    In Proton, for example, most of the rest mass is relativistic mass of quarks, moving at relativistic speeds.

    Quarks are quite light, but if we go deeper, the rest mass of quark is also an illusion - all particles have rest mass = 0, and what we call mass is a result of interaction of a partcile with Higgs field.

    Does Higgs have rest mass > 0?
  2. jcsd
  3. Jun 2, 2010 #2


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    This is a nice popular article on the origin of mass from on of the QCD fathers.

    Where he notes that more than 90% of all mass of matter are due to "confined energy" of the pure energy as in "massless" photon and gluon fields.

    The residual mass are attributed to masses of quarks (and electrons).

    The higgs particle/mechanism, which we should note isn't yet found, and is IMO still a theoretical idea motivated by expectations from the consistency of SM rather than confirmed fact, is believed to be very heavy, 300000 times the mass of the electron.

  4. Jun 2, 2010 #3
    What gives rest mass to Higgs itself?
  5. Jun 2, 2010 #4


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    Good question but I don't think there is supposed to be an answer to that in the SM?

    Maybe someone else can provide som meaningful answer to this, but as far as I understand this question is one of the ways in which the higgs mechanism does not explain mass without mass.

    I think the idea of mass without mass, as just "confined energy" is interesting, and this somehow connects to the meaning on why there is stable confinement of energy, and also the meaning of "confinement" (I don't mean quark confinement here though) implicitly refers to some kind of index or state space in general, and ordinary 3D space in the more specific meaning here.

    I personally think the origin of mass requires some new ideas. I don't think focusing on the higgs itself will solve the deepest sense of this question.

  6. Jun 2, 2010 #5


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    I this thread https://www.physicsforums.com/showthread.php?t=254612 there is an old discussion of Frank's book Lightness of Being, it's a popular level book rather than anything else, but I found hints of some interesting ideas on the "NATURE OF SYMMETRY" reading that book, that is to my liking. I strongly associate this to the recent discussions of nature of physical law (https://www.physicsforums.com/showthread.php?t=403596) , since to a large excent symmetries are the essence of laws, or a compect representation thereof.

    Last edited by a moderator: Apr 25, 2017
  7. Jun 2, 2010 #6

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    Somehow I don't think "fundamental" is a good word for what is "the mass it would have if the laws of physics were different than they are".

  8. Jun 3, 2010 #7


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    I don't understand this enough to say that I have a coherent picture of this, but if I'm not mistaken several coupling constants as well as the higgs actual mass (not just the idea that it has mass) are still not predictable from the regular SM, and there are rather extensions with a diversity of predictions.

    The simple idea of mass from relativistic mass as confined energy just begs two further questions.

    What is energy, the reason for "confinement" of energy in space, and what is space. Probably the questions are different views of the same bigger question.

    But an issue I see with the higgs ideas it is that it is a somewhat constructed mechanism that appears to be almost like a fifth force? This seems unsatisfactory and slightly ad hoc. So the higgs still begs the questions: what is the higgs field? and what determines it's action, if it does not follow from the known standard actions?

    As far as I understood, these question have no answers, or do they? Until they do, isn't the entire "higgs giving mass to others" more like a bookkeeping thing that as an satisfactory explanation?

    I would love it someone that has deeper knowledge on these details could jump in.

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