2 - Continuum (scaling) limits of lattice fields theories (triviality of lg q in d 1=y4 dimensions
3 -Results and problems near the interface between statistical mechanics and quantum field theory]]>
Abstract : An energy band in a solid contains an infinite number of states which transform linearly as a space group representation induced from a finite dimensional representation of the isotropy group of a point in space. A band representation is elementary if it cannot be decomposed as a direct sum of band representations; it describes a single band. We give a complete classification of the inequivalent elementary band representations.]]>