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Put a quark in it

  1. Aug 5, 2008 #1
    Ive noticed when we are viewing the quark table in particular its charmness, and strangeness we know; c quark has a charmness of +1, but the strangeness of an s quark = -1. I would like to better understand why. Is it not thought that the s quark has a strangness of +1?
  2. jcsd
  3. Aug 5, 2008 #2


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    It's purely conventional. The reason it was assigned minus one is a historical one.
  4. Aug 6, 2008 #3
    Lol. understandable... I knew there had to be a more as you put "conventional" meaning. It was beginning to really put a damper on the day. Thanks nrged.
  5. Aug 7, 2008 #4


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    The reason s has the "wrong-sign" strangeness is because before people understood about quarks, they understood Kaons. There was a particle called the "K+" - as it had electric charge +1, they understandably decided to give it strangeness "+1" as well.

    Then along came the quark model, where the "strangeness" quantum number was affiliated with the presence of a strange quark. The only problem was that the K+ was described in the quark model as a (up - ANTIstrange) bound state. So they had to assign the strange quark's strangeness quantum number as -1 to be consistent.

    Hey, Ben Franklin decided that the currents flow from positive charge to negative charge. He had a 50-50 chance of being right, and at the time there was no way to measure the charge of the electron (in fact, they didn't even know about electrons!) - so now the convention is set, and currents look like they flow the wrong way! Of course it doesn't really matter, but it's kinda amusing. :wink:

    That's the problem when charges are assigned BEFORE people understand what the "fundamental" physics is. But we do what we can.
  6. Aug 7, 2008 #5
    Thats right blechman, and it is rather humorous when you think about the flow of currents and how they have been positioned or assigned through strangeness. As in Ben Franklin's case, Sometimes you've got to learn things the hard way. lol. Thanks for your insight.
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