Quantum Many Body Systems and Strongly Correlated Electrons II
Basic Course given by Michele Fabrizio
Start Date
End Date
Tue: 11:00-13:00
Wed: 11:00-13:00


21/11 Propagation in imaginary time and Matsubara formalism. Single- and two-particle Green's functions, and relationship with physical obervables.

22/11 Perturbation theory in imaginary time: general formalism and Wick's theorem.

28/11 Perturbative expansion of the single-electron Green's function in powers of the electron-electron interaction. Feynman diagram representation of the perturbation series.    

29/11 Dyson equation, self-energy and its physical meaning.

5/12 Perturbative expansion  of the two-electron Green's function in powers of the electron-electron interaction. Four-leg vertices and Bethe-Salpeter equations.

6/12 Three-leg vertices and linear response functions in perturbation theory. 

12/12 Conservation laws and Ward-Takahashi identities.

13/12 Conserving approximations and few examples.  

19/12 Luttinger-Ward functional, free-energy and Luttinger's theorem

 19/12 Diagrammatic expansion in other perturbations: electron-phonon/photons/etc.. coupling, external fields, impurity potential.