1. lecture 3 1

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3. 3

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6. Dirac 1927: search for a wave equation, in which the time derivative appears only in the first order ( Klein- Gordon equation: second time derivate is needed ) 6

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11. positron 11

12. Dirac equation 12

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21. . Suppose that the proton is a collection of 3 quarks (zero binding energy). The proton mass is the sum of the three quark masses: mass (quark ) = M(proton)/3 =>one obtains the correct magnetic moment of the proton. Suppose that the proton is a collection of 3 quarks (zero binding energy). The proton mass is the sum of the three quark masses: mass (quark ) = M(proton)/3 =>one obtains the correct magnetic moment of the proton 21

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25. The vector current and the axial vector current can be measured by the electromagnetic and by the weak interactions. The tensor, the scalar and the pseudoscalar densities cannot be measured. 25

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29. 1826 conversion of magnetism into electricity 29

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31. Quantum physics 31

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38. 38  Dirac equation with interaction of electron and photon  Maxwell equation

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46. 46  gauge theory

47. Intrinsic connection between charged fields and space-time

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49. Arnold Sommerfeld, 1916 49

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51. fine-structure constant =0.00729735253 51

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56. refdn dd Kl renormalization of the electron mass kl12 56

57. refdn dd Kl renormalization of the electric charge kl12 57

58. Quantum Field Theory: Finestructure constant becomes function of energy or scale due to quantum fluctuations of electron-positron pairs => partial screening of bare charge of the electron at distances less than the compton wavelength of the electron 58

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61. + 61

62. OPAL ALEPH L3 DELPHI 62

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64. Non-Abelean gauge theories 64

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66. Pauli did not publish his theory, since he did not know, how to introduce the masses for the gauge bosons. 66

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68. Yang and Mills did not mention the letter of Pauli in their paper, published in Phys. Rev. They disregarded the problem how to introduce the masses of the gauge bosons. ( In QCD no masses are needed.) 68

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72. Abelean gauge theory ( e.g. QED): The gauge boson interacts only with the fermions. Non-Abelean gauge theory ( e.g. QCD): The gauge bosons interact with the fermions and with the gauge bosons - (e.g. in QCD: gluon-gluon scattering ). 72