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the observed masses of the particles R. Feynman

  1. May 14, 2008 #1
    "...the observed masses of the particles.." R. Feynman

    Feynman wrote: "Throughout this entire story there remains one especially unsatisfactory features: the observed masses of the particles, m. There is no theory that adequately explains these numbers. We use these numbers in all our theories, but we do not understand them - what they are, or where they come from. I believe that from a fundamental point of view, this is a very interesting and serious problem." end of quotation

    Is this statement by Feynman from 1985 still true?
  2. jcsd
  3. May 14, 2008 #2
    Which mass are you talking about ? Your quotation is out of context : where was that written ?

    The masses of fundamental particles, your mass and the ones of familiar objects around you, or the electromagnetically invisible masses that show up gravitationnally at astronomical scales ? At different levels, all those different masses are not satisfactorilly explained. But you need to focus the discussion, otherwise if you want to talk about all of them, you should open separate discussions, since those are independent problems.
  4. May 14, 2008 #3

    The quote is on p152 from "QED, The Strange Theory of Light and Matter".
    Last edited: May 14, 2008
  5. May 14, 2008 #4
    So I suppose you are refering to the masses of fundamental particles. Assuming this is correct, do you want to talk about the Higgs mechanism in electroweak spontaneous symmetry breaking, or about the so-called hierarchy problem (fine-tuning and naturalness) ?
  6. May 14, 2008 #5

    I have not referred to any particular particles. I'm simply asking if Feynman's statement is true or not?
  7. May 14, 2008 #6
    I already told you that Feynman statement is still valid, independently of which type of mass you are interested in. I do not ask you whether you refer to any specific or "particular" particle. I ask you whether you refer to fundamental particles, like e.g. quarks, and by contradistinction to, for instance, the proton.

    The Higgs mechanism allows you to have massive fundamental particles in the standard model.
    Last edited: May 14, 2008
  8. May 14, 2008 #7

    If we have no clue where the mass comes from, then how do we know it is not simply "mechanical" mass instead of "electromagnetic" mass or "inertial" mass?
  9. May 14, 2008 #8
    This is not a discussion. Trying to address your own questions, I ask you another question to clarify, which unfortunately you do not seem to understand, therefore you prefer to ignore it instead of admiting you do not understand my question. You want to use Feynman's quotation to bring in your own personal views on a mechanical model of fundamental particles. This is unfair. Feynman's quotation has a context which I wish you would like to understand. But you do not understand the currently admitted Standard Model of fundamental particles, so how can you claim it is wrong ?

    Should I continue feeding the troll ?
  10. May 14, 2008 #9
    I'm simply here to learn. I offer my apology since my way of learning bothers you.
  11. May 14, 2008 #10
    I am here for the same reason. I can share what I know, and I am happy to be corrected when my claims are wrong.

    The problem with any kind of mechanical model of fundamental particles is that is has to be quantum. That severely reduces intuition.
  12. May 14, 2008 #11
    I guess that Malcolm MacGregor (retired from LLNL) and one of his mentors must be all wet when they propose that the electron might have mechanical, nearly spherical, mass with a point charge located at its equator of that mechanical mass that is spinning at near relativistic speed and with a title angle of 55 deg to accommodate the spin nature of the electron.
  13. May 14, 2008 #12
    I do not take authority arguments as acceptable.
    What is this good for ? Why should we need to change from a simple, well motivated mathematical formalism (Dirac equation) which does explain the spin to a complicated mechanical model. Can you reproduce the accuracy of the calculations for the electron and muon magnetic moments ?
  14. May 14, 2008 #13
    If memory serves me right, then the answer is Yes. MacGregor has worked out the moments. It would be helpful if you had access to MacGregor's book "The Enigmatic Electron". They might also have the book by Myron Evans and Jean-Pierre Vigier titled "The Enigmatic Photon - Volumes 1-3".
  15. May 14, 2008 #14
    Has he not calculated 55 deg to reproduce the magnetic moment ? This is very different from being able to calculate it, like in QED. Besides, this still does not account for the muon. And QED can do even much more
  16. May 14, 2008 #15
    If QED is so great, then why do we have QCD? MacGregor is just one man, who in some circles might be called a crackpot or quack, and yet he is hard at work together with other professional scientists trying to sort out some of the problems with the mass of the electron and its other properties. Remember - this thread is about mass, yes?
  17. May 14, 2008 #16
    You question is similar to asking "if you have a kitchen, then why do you have a bedroom ?".
  18. May 14, 2008 #17
    Not really. I'm comparing a Quantum Electric Kitchen with a Quantum Colored Bedroom.
  19. May 14, 2008 #18
    You got me once again.

    QED is for eletromagnetism, QCD is for the strong force. Those are different interactions.
  20. May 15, 2008 #19


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    Since we have more than one fundamental force? :biggrin: QED is, as the name suggests, the quantum field theory of electromagnetism.

    And yes, mass in the standard model are accomplished by interaction with the Higgs field.
  21. May 15, 2008 #20


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    you can sleep in the kitchen!
  22. May 16, 2008 #21
    Just how many Higgs particles have been measured so far?
  23. May 16, 2008 #22
    Being a strong proponent of the GUT, it seems that QCD is a simple bandaid on top of QED that allows some to keep the two phenomena separated instead of trying to find the missing link. The nature of the core is vastly different from the electrons, but the core still uses almost the same orbital structure as far as experiment and theory show. It shows spin, angular momenta etc etc.

    For me, the only real difference between QED and QCD is the mass difference since parity (chirality in organic chem terms) is not much affected. Yep, I'm back to that nasty and still undefined phenomenon known as "mass."

    OK, now who's turn is it on the kitchen floor?
  24. May 16, 2008 #23
    There we go...
    Once again, you clearly have no clue. Would you say
    Really, QED deals with electrodynamics, QCD deals with the strong force. Both theories have been succesfully tested in our laboratories. Do you know many theories predicting more than 10 digits on observables !? Name any (that you do not reject). QCD has been tested on many orders of magnitudes. Please take a look at that :
    Figure 16.7.
    If you are not impressed, then please go back to your 80 personal books or so, and try to understand. This plot is amazing.

    You really have no clue, this is desperate... The difference between QED and QCD is U(1) versus SU(3). And yes, we gave Nobel prizes to those people, so if there is anybody calling other people by names, that would be the ones claiming QED and QCD must go to the rubbish bin...
  25. May 16, 2008 #24


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    The point is that we have a theory (or many different theories) that predicts the existence of the Higgs boson and how mass is generated. And this can be done with the LHC. This is how real physics works - one does theories that accounts for all old phenomenons and make testable predictions.

    Then if you don't know the difference between QED and QCD or what so ever, I only feel that you have not studied hard enough. You know, there is a reason why quantum physics is the paradigm today. It needs quite large anomalies to leave that.

    Try for instance to make up a new, non quantum, theory for superconductivity, that is not Ad Hoc. And a theory for replacing Quantum Electro Dynamics, that have predicted and reproduced experimental values of the order 8th digit or so.
  26. May 16, 2008 #25


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    The core? you mean nucleons right? ;)

    Again, you have not studied enough. Maybe buy a new book, how about the new edition of griffiths elementary particles, that will soon be available?
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