Sumários
Discussion of the homework exercises
20 Março 2020, 08:30 • Nuno Barros
Discussion of the solutions of the exercises of the previous weeks.
Dirac equation (continuation). Introduction to QED
18 Março 2020, 08:30 • Nuno Barros
- Dirac equation
- Revision of spin
- Introduction of helicity. Helicity eigenstates.
- Charge conjugation. Intrinsic parity of Dirac particles.
- Introduction to QED
- Interaction by particle exchange
- Time-ordering diagrams.
- Feynman diagrams. Virtual particles
- Feynman rules for QED
Interaction cross section. Introduction to Dirac equation.
13 Março 2020, 08:30 • Nuno Barros
- Derivation of Interaction cross section. Lorentz-invariant formulation
- Transformation to laboratory frame.
- Introduction to Dirac Equation
- Klein-Gordon equation
- Probability density and current
- Dirac equation
- Covariant formulation of the Dirac equation
- Solutions of the Dirac equation
- Free particle at rest
- Plane-wave solutions
- Interpretation of negative energy solutions
- Feynman-Stückelberg interpretation
Not Taught.
11 Março 2020, 08:30 • Nuno Barros
In-person classes suspended the day before. Not enough time to make arrangements for remote teaching. Subject covered in next TP class.
Decay rates and cross sections
6 Março 2020, 08:30 • Nuno Barros
- Review of previous lectures
- Demonstration of properties of the Dirac delta function
- Fermi's Golden Rule
- Non-relativistic formulation
- Phase space and wave function normalisation
- Lorentz-invariant formulation
- Particle decays