Beyond the Standard Model

Summary

The unification of physical law [pdf] is an ongoing theme in physics.
- Historical Unification
  - Newton's theory of universal gravitation unified the …
    - terrestrial gravitation described by Galileo in his laws of falling bodies and projectiles and …
    - celestial gravitation described by Kepler in his three laws of planetary motion.
  - Maxwell's equations of electricity and magnetism (E&M) or electromagnetism unified the theories of …
    - electricity as described by Franklin, Coulomb, et al. with …
    - magnetism as described by Gilbert, Michell, et al. and then subsumed …
    - optics as described by Hooke, Huygens, Newton, Young, et al.
  - In the early Twentieth Century …
    - gravitation was expanded into the theory of general relativity (GR) by Einstein;
    - electromagnetism was expanded into the theory of quantum electrodynamics (QED) by Feynman, Schwinger, Tomanaga, and Dyson; and
    - the strong force was described in the quantum chromodynamics (QCD) of Gell-Mann and Zweig; but
    - the weak force was not described by an independent theory of what is sometimes informally called quantum flavordynamics (QFD).
  - The electroweak theory (EWT) of Glashow, Weinberg, and Salaam extended …
    - quantum electrodynamics, which had been described, to include …
    - quantum flavordynamics, which had not yet been described.
  - The standard model of particle physics …
    - is the combination of …
      - electroweak theory (EWT) and
      - quantum chromodynamics (QCD)
    - is not a theory unto itself
- Conjectural Unification
  - By extension, there should probably be a grand unified theory (GUT) that would unite …
    - electroweak theory with …
    - quantum chromodynamics.
  - By extension, there should also be a theory of everything (TOE) that would unite the four fundamental forces of nature …
    - gravity
    - the strong force
    - the weak force
    - electromagnetism
  - Some candidates for a theory of everything include …
    - string theory, M theory, brane world, etc.
    - supersymmetry
    - E8
Science is reductionist in nature.
- Complex entities are built from elementary constituents.
  - Everything is essentially "atomic".
- The laws describing the behavior of elementary constutents are few in number.
  - All additional "laws" can be dervied from these few laws in principle.

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