torsdag 28 april 2011

The Standard Model, -/+.

Wilzcek ina talk at the awards session, EPS-HEPP meeting, Krakow, July 2009. I was looking at his Higgs mechanism, and aimed at comparing it to Mattis, when I found this very clear resume'.

What are the shortcomings of the standard model?

  • In the standard model as it comes, the pattern of groups, representations, and (especially) hypercharges is a patchwork.
  • In the standard model as it comes a great discovery of recent years the existence of small non-zero neutrino masses, appears gratuitous. One can accommodate those masses using non-renormalizable, mass dimension 5 operators, but even then the fact that masses of neutrinos are far far smaller than masses of their charged lepton cousins lacks context.
  • In the standard model as it comes there is no evident link between the standard model and the remaining major force of Nature, i.e. gravity. - That is, GR is not here? (my comment)
  • In the standard model as it comes there is no evident accounting for the bulk of the mass in the universe, i.e. the dark matter and dark energy.
  • In the standard model as it comes there is no explanation for the empirical smallness of the P and T violating angle (phi) term.
  • Masses and mixing angles among quarks and leptons are not constrained by any deep principles, and this sector of the standard model brings in a plethora of unworthy “fundamental” constants.
  • The triplication of families is gratuitous. -The fourth generation?
What are the great lessons of the standard model?
  • The gauge principle translates mathematical symmetry into physical law.
  • The observed interaction symmetries and fermion representations fit into a larger, unifying symmetry and unifying representation very economically.
  • Gauge symmetry can be spontaneously broken.
  • Coupling constants evolve with distance, or energy.
Beyond the Standard Litany: LOSP and Higgs Portal: Lattice Lattice Gauge Theory (March
2010) PoS EPS-Hep 2009, hep-ph1003.4672

2 kommentarer:

  1. Ulla,
    This is a good listing of the pro's and con's of the standard model in relation to other issues.

    But we should not think that these conclusions are right necessarily because it merely points out problems with the theory so in a way talks still in its terms and does not save what may be of value in it.

    Matti's ideas are way beyond these issues. And my own sees the list as cleaver but not good at leading up to a good explanation.

    But this is useful in our explorations, a stepping stone- even if we are talking about things that we really have not made clear like what a "generation" means. My last posts have a wider answer for all of that than even I imagined a year ago.

    Wouldn't it be ironic if you were in the middle of two very complicated theories at the frontier of things? What are the chances? What the arrangement and purpose in our human experience of terms?

    I wish I understood Pikanen's 89 and such better but his conclusions I can read as right on.

    Today, in my less readable posts I saw three aphodels at last for spring and thought of the war protests in cambridge and their six fold symmetry of you- and Kea, I need a Kea fix.

    The PeSla

  2. These points are simply quoted from the text, and is Wilzceks view. But we must be able to learn also from other theories, and this is one of the most interesting, in my mind. To be able to interpret TGD you also need to somehow understand how other think.

    In fact, I have long sought for this kind of list, so here it is. Much simpler you cannot express it.