I don’t really know how to describe this notes, they are just a supplement to the main notes but well organised in my opinion and with multiple inputs from other books. Very few formulas will be derived, however the goal is to try to explain the physics of all of them.
In this notes you will find a brief introduction to Classical Field Theory and a short introduction to Special Relativity. We continue by introducing the most common fields in QFT: real and complex scalar field, dirac field and the EM field. Then, we introduce one of the most important tools in the calculation of transition amplitudes, the \(S\) matrix, which allow us to explore the Feymann rules of QED in the next section. Finally, the notes end by explaining how to perform calculations of lifetime and cross-section.