# General Theory of Green Functions

We start with the general theory of Green functions:

#### Hedin, L. and S. O. Lundqvist. “Effects of Electron-Electron and Electron-Phonon Interactions on the One-Electron States of Solids”. in Solid State Physics 23 (1969) 1 [DOI].

The goal is to derive Hedin's equations, and grasp a physical understanding of Green functions, self-energies, spectral functions, response functions and vertex corrections.

It is important that these ideas be connected the single-particle quantum physics. The connection to the experimental measurements is also to be developed.

Along with the main article above, there is a need for other resources as:

- Fetter, A. L. and Walecka, J. D. “Quantum theory of many-particle systems”. Dover (2013).
- Gross, E. K. U. et al. “Many-particle Theory”. Taylor & Francis (1991).
- Bruus, H., and K. Flensberg. “Many-body quantum theory in condensed matter physics”. Oxford University Press (2004).
- Jishi, R. A. “Feynman diagram techniques in condensed matter physics”. Cambridge University Press (2013).
- Ziman, J. M. “Principles of the Theory of Solids”. CUP (1972).
- Kittel, C. “Quantum Theory of Solids”. Wiley (1963).
- Held, K., et al. “Hedin equations, GW, GW+DMFT, and all that”. arXiv:1109.3972.
- Pines, D. “Elementary excitations in solids”. Perseus (1966).

*Notice: This section is subject to updates.*