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Whence Charm ?

  1. Apr 30, 2010 #1

    blechman

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    Whence "Charm"?

    The quarks have very quirky names! All of them have an origin:

    * (up, down) refer to isospin states.
    * strange refers to "strange decays" that were, well, strange!
    * (bottom, top) are derived from "beauty" and "truth" ("Beauty" still is used synonymously with "bottom").

    But I have no idea where the name "charm" comes from. I have heard two interpretations:

    1. Since charmonium lives so long, it is said to have a "charmed" life!

    2. [From Wikipedia]: "The name appears to derive from Lafcadio Hearn's Japan: An Attempt at Interpretation. Chapter 2 is called 'Strangeness and Charm.'"

    I was wondering if anyone here knew which (if any!) is correct?
     
  2. jcsd
  3. Apr 30, 2010 #2
    Re: Whence "Charm"?

    In Richter's lecture, he talks about GIM paper and mentions that "charm" had been coined by Glashow some time earlier. The original GIM paper lead me to :
    Elementary particles and SU(4)
    Bjorken and Glashow
    Phys. Lett. vol 11 num 3 (1964)
    where indeed one finds the name "charm". None of the references in this paper seems to mention the name "charm" (I checked the 3 first, associated with the first mentioning of the new flavor coined "charm").

    If this interpretation is true, oddly enough "charm" would not stem from the elegance of the GIM mechanism (which I would have guessed a priori). Rather, it would first be written in the above paper
    this is part of the GIM mechanism, but missing the main part

    If interested in the GIM mechanism, one can check scholaropedia
     
  4. Apr 30, 2010 #3

    blechman

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    Re: Whence "Charm"?

    From a friend:

    "Glashow had written an article with Bjorken suggesting a possible fourth quark.... 'We called our construct the charmed quark,' recalled Glashow, 'for we were fascinated and pleased by the symmetry it brought to the subnuclear world.' "

    The Hunting of the Quark, p. 210.
     
  5. May 1, 2010 #4

    Haelfix

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    Re: Whence "Charm"?

    Glashow definitely coined the term. But beyond that, where he got it from is a source of dispute afaik. I've heard the 'charmed life' and 'strangeness and charm' hypothesis several times before.
     
  6. May 1, 2010 #5

    tom.stoer

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    Re: Whence "Charm"?

    The standard model with an odd number of quarks is inconsistent to to gauge anomalies from chiral fermions. Therefore we need an even number of quarks. Perhaps the reason for "charme" is that its discoverey saved the SM from being inconsistent.
     
  7. May 1, 2010 #6

    blechman

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    Re: Whence "Charm"?

    that's true, but this is before the SM! Weinberg's paper was 2 yrs later.
     
  8. May 2, 2010 #7
    Re: Whence "Charm"?

    The only thing I'm certain about regarding quarks is the derivation of the name from 'Finnegan's Wake' by Joyce. "Three quarks for muster mark..." Color makes sense, sort of, but charm, strange, up, down? How can brilliant people apply such whimsy to something so very dry?
     
  9. May 2, 2010 #8

    clem

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    Re: Whence "Charm"?

    "Color makes sense, sort of"
    sort of how?
     
  10. May 2, 2010 #9
    Re: Whence "Charm"?

    Color charge has no real analogue in our everyday experience, so why not assign it a value based on something that IS common experience? Red, Green, Blue.
     
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