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Understanding Fundamental Constants in Particle Physics and Beyond

Delve into the significance of fundamental constants in modern science, from particle physics to cosmology, exploring their role in the Standard Model and beyond. Discover the intriguing history and implications of these constants in shaping our understanding of the universe.

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Understanding Fundamental Constants in Particle Physics and Beyond

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  1. Time Variation Fundamental Constants and their Harald Fritzsch LMU Munich

  2. - fundamental constants the problem of modern science

  3. particle physics nuclear … atomic … laser … solid state … astro … cosmology fundamental constants =>

  4. ==> chemistry, biology, ...

  5. - Fundamental constants Standard Model

  6. - Standard Model gauge theories

  7. - first gauge theory QED

  8. - QED 2 fundamental constants

  9. 1964 ===> electroweak gauge theory U(1) x SU(2)

  10. gauge theory of the Strong Interactions

  11. - M. Gell-Mann G. Zweig M. Gell-Mann G. Zweig 1964 quarks

  12. - ( ) u ( ) p d n s electric charge:

  13. - 1971 color q=> q q q SU(3,c)

  14. - - Hadrons - white states

  15. - 1971 - 1972 QCD Fritzsch & Gell-Mann

  16. 8 gluons

  17. - 1973: Standard Model SU(3) x SU(2) x U(1) 2 ==> 28

  18. problem ===> 28 fundamental constants

  19. Newtons constant G 1 fine structure constant 1coupling constant of strong interaction 1coupling constant of weak interaction 1mass of W boson 1mass of Higgs boson 1masses of 6 quarks and 6 leptons 12 flavor mixing of quarks 4flavor mixing of leptons 6 - 28

  20. 28

  21. (22 related to fermion masses)

  22. - MeV masses 100 10 1

  23. - Arnold Sommerfeld, 1916 fine-structure constant

  24. - electrodynamics + relativity + quantum theory

  25. QED

  26. partial screening + - + + - - - -

  27. fine-structure constant ==> function of energy +

  28. - LEP: ~ 1/127

  29. - nucleon mass fundamental constant ? ==> QCD

  30. - quark masses ==> 0 mass <=> field energy

  31. dimensional transmutation

  32. nucleon mass ( quark masses => 0 =

  33. Experiments: ~ 250 MeV mass <==> confined field energy

  34. real world: QCD u d s QED M (proton) = 860 + 21 + 19 + 36 + 2

  35. Standard Model: fundamental constants in our universe universal

  36. Are the fundamental constants functions of time and space?

  37. - function of energy

  38. - ? function of time?

  39. About 1.8 billion years ago, in Gabon, Westafrika. Natural Reactor, which operated about 100 million years. High concentration of uranium 3.7% U 235 at that time (today 0.72 %) Moderator: water from river Oklo Oklo Phenomen

  40. discovery: 1972 Natural reactor ( output: ~ 100 kw )

  41. Oklo zones

  42. - samarium: neutron capture Sm(149) + n => Sm(150) + photon cross section about 80 kb nuclear resonance: E = 0.0973 eV

  43. - change of resonance position less than 0.1 eV in 2 billion years constraint for fine-structure constant: ( Dyson, Damour)

  44. Change of alpha per year must be less than per year (if no other parameters change) ==>constraint questionable -16 10

  45. - limits on time variation of constantes, related to stable matter: fine-structure constant mass of electron QCD scale quark masses

  46. time variation of QCD scale:

  47. u / d - quarks ~ 20 MeV of proton mass

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