ABSTRACT

U NIFYING THEMES, CONCEPTS, STRUCTURES, AND IDEAS are the cornerstones of understanding physical reality. The remarkable

success of condensed matter physics is intimately related to the existence of a few powerful paradigms that operate throughout a vast field with rather blurry boundaries stretching from the realm of atomic physics to the gates of astrophysics and from fundamental problems that, typically, constitute the object of particle physics or cosmology to applied problems addressed, for example, by materials science and biophysics. Condensed matter, this Middle Earth of physics, is a rich and diverse field that provides wide avenues for transferring themes among different areas and serves as the battleground of reality for many great ideas. This is also an extremely successful field due to the experimental accessibility of condensed matter systems, which promotes a fruitful synergy between theory and experiment. The knowledge acquired in this field enables exquisite control of materials properties and constitutes the bedrock of present-day information technology. Historically, the ability to control and exploit condensed matter systems was always intimately linked to the technological progress of humankind, from the Stone Age to the “Silicon Age.” Recent developments in condensed matter physics clearly illustrate the

antinomy between our desire for complete understanding and the joy of discovering something new. As a result of these developments, the researcher’s status of “being on the road” will be preserved, at least in the foreseeable future. This should be great news, for who would really want to reach the end of the road, the theory of everything, the One Ring?