Progress in Unifying Condensed Matter Theory

Abstract

Over the years, experimentalists have uncovered an array of fascinating properties of condensed matter. The initial response of theorists has been to treat each new property as a separate problem to be solved, with the result that condensed matter theory presents the appearance of “a different Hamiltonian for every problem.” But there has always been an undercurrent of work aimed at searching out common ground, and of reconstructing disparate theories from a more universal basis. Ultimately, the same wavefunctions and energy levels should explain all the properties of a given material in a given state. Here we sketch development along this line, and note how it is useful in continuing research.