The fascinating phenomenon ferromagnetism is far from being fully understood, although it surely belongs to the oldest problems of solid state physics. For any

Ferromagnetism is a form of magnetism that can be acquired in an external magnetic field and usually retained in its absence, so that ferromagnetic materials ar

This book is a self-contained advanced textbook on the mathematical-physical aspects of quantum many-body systems, which begins with a pedagogical presentation

Ferromagnetism is a form of magnetism that can be acquired in an external magnetic field and usually retained in its absence, so that ferromagnetic materials ar

Little do we reliably know about the Mott transition, and we are far from a complete understanding of the metal --insulator transition due to electr- electron i