1. Fundamental principles of particle physics G.Ross, CERN, July08

2. Fundamental principles of particle physics G.Ross, CERN, July07 Introduction - Fundamental particles and interactions Symmetries I - Relativity Quantum field theory - Quantum Mechanics + relativity Theory confronts experiment - Cross sections and decay rates Symmetries II – Gauge symmetries, the Standard Model Fermions and the weak interactions Outline http://www.physics.ox.ac.uk/users/ross/cern_lectures.htm

3. Fundamental principles of particle physics G.Ross, CERN, July07 Fundamental Interactions

4. Fundamental principles of particle physics G.Ross, CERN, July07 Fundamental Particles Fundamental Interactions

5. Fundamental principles of particle physics G.Ross, CERN, July07 Fundamental Particles Fundamental Interactions

6. Fundamental principles of particle physics G.Ross, CERN, July07 Fundamental Particles Fundamental Interactions Strength Size

7. E r

8. Units Natural Units Length : L Time : T Energy : E or Mass : m Choose units such that : 1 unit left : choose

9. Natural Units Dimensionless- same in any units

10. Fundamental Interactions and sizes Atomic binding : Nuclear binding :

11. Elementary particles Leptons : Quarks : Isador Rabi 1937 “Who ordered the muon?”

12. Elementary particles Leptons : Quarks : Hadrons :3 strong “colour” charges

13. Elementary forces

14.  The strength of the force  Exchange forces Experiments conducted in momentum space : Electromagnetism Photon “propagator” Feynman diagram

15.   Experiments conducted in momentum space : Exchange forces Electromagnetism

16. Feynman diagram Application to a scattering processes

18. (Q 2 )  In momentum space : g Exchange forces Strong interactions

19. (Q 2 )  In momentum space : Z Exchange forces Weak force Yukawa interaction

20. (Q 2 )  G Exchange forces Gravitational force

21. (Q 2 )  G Exchange forces Gravitational force