ABSTRACT
One need not apologize when considering the applications of physics to down-to-Earth objects.
Physics rightly deals with both formal foundations (like supersymmetry) and the properties of materials (like superconductors). Supersymmetry and superconductors do not appear to have much in common. However, the surprising overlap between abstract ideas and their applications to real materials can be rewarding. For example, the generalizations of ordinary phase transition (like melting) are seen in theoretical particle physics. The applications of scale invariance (big looks like small) have helped to unify material physics, particle physics, and cosmology.
