| We study two metallic systems in which the electronic correlations determine their physical properties. The first system is a three-dimensional, weak-ferromagnetic metal at zero temperature. We study the phase diagram of the quantum liquid and find a new type of low-temperature superconducting state in the neighborhood of the ferromagnetic phase transition. The second system is a one dimensional metal. For the first time the Luttinger theorem is proven for a Luttinger liquid. At the end we discuss the application of Compton scattering for mapping the Fermi surface of metals in different dimensions. |
