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Basic interactions in the Standard Model

  1. Feb 14, 2016 #1

    Is there a list of basic interactions in the standard model? Does anyone know where I can find this list of basic interactions in the standard model?
  2. jcsd
  3. Feb 14, 2016 #2


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    What is a "basic" interaction (and what is a non-basic one)?
    As usual, the Wikipedia article gives a good introduction.
  4. Feb 14, 2016 #3
    I'm actually not sure which one is considered basic and non basic, I'm that lost. haha. Is a beta decay a basic interaction? Could you link the wikipedia page?
  5. Feb 14, 2016 #4


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  6. Feb 15, 2016 #5


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    The fundamental interactions meant to be described by the Standard Model are the : weak interactions, strong interactions and electromagnetic interactions.
    The beta decay you mentioned is a weak process...
  7. Feb 17, 2016 #6
    I am assuming you are referring to decays and interactions between particles.

    A beta decay is one involving the weak interaction, as I see ChrisVer also mentioned.

    This huge document from the Particle Data Group (1600 pages) has information on pretty much everything in the standard model: http://pdg.lbl.gov/2015/download/rpp2014-Chin.Phys.C.38.090001.pdf

    For example, the first 90 or so pages are dedicated to decays of various sorts. Depending on your level the way it is written could of course be a little overwhelming, but those are my five cents at least. Enjoy!

    O an on page 80, I noticed, you have baryon decays, which might be what you are looking for!

  8. Feb 17, 2016 #7
    Mathematically speaking, "interactions" in SM correspond to Lagrangian terms which include more than one field.


    (the terms which include only one field are "kinetic terms", they describe propagation of particles through space without interaction, such as electron moving through empty space. Essentially, "electron interacts with itself" in such a way that it simply moves in a straight line with constant speed.
    There are two "one field" terms which describe self-interaction of Higgs field which can't be seen as propagation; instead, they are responsible for phi=0 not being a minimum of energy).

    Let's take the inventory of interaction terms:

    - B*psi term (weak hypercharge field * fermion field)
    - W*psi term (weak isospin field * fermion field)
    - G*q term (gluon field * quark field)
    - B*phi term (weak hypercharge field * Higgs field)
    - W*phi term (weak isospin field * Higgs field)
    - phi*psi term (Higgs field * fermion field)

    Gravity does not exist in SM.

    Thus we have six interactions in SM.
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