This document summarizes a lecture on Feynman rules for quantum field theory. The lecture introduces perturbation theory and elementary Feynman rules for calculating amplitudes. It discusses the interaction picture and S-matrix approach. Examples are provided for calculating amplitudes and probabilities for basic processes, including decay rates and lifetimes. The goal is to explain the fundamental concepts and tools used in quantum field theory calculations.

1. Feynman Rules
Lecture 2 on QFT by Hasan Mohammad

2. Introduction
Nobel Prize in Physics 1965
Lecture Content
 Interaction Picture
 Perturbation Theory
 Elementary Feynman Rules
 Calculating Amplitudes
 Example Exercises (1 & 2)
 Rates of Decay and lifetimes

3. Interaction Picture- S Matrix
• Schrodinger
• Interaction
• Heisenberg.

4. Interaction Picture- S Matrix
• Schrodinger
• Interaction
• Heisenberg.

5. Interaction Picture- S Matrix

6. InteractionPicture-Hamiltonian

7. Interaction Picture-Hamiltonian

8. Perturbation Theory

9. Perturbation Theory

10. Calculating Amplitudes

11. Calculating Amplitudes

12. Calculating Amplitudes

13. Calculating Amplitudes

14. Calculating Amplitudes

16. Propagators

17. Example (1)

18. Propagators

19. Example (1)

20. Example (1)

21. Example (1) Amplitude

22. Probability

23. Example (2)

24. Example (2)

25. Example (2)

26. Example (2)

28. THANK YOU VERY
MUCH