Scaling Theory of a Compressibility-Driven Metal-Insulator Transition in   a Two-Dimensional Electron Fluid
  We present a scaling description of a metal-insulator transition in two-dimensional electron systems that is driven by a vanishing compressibility rather than a vanishing diffusion coefficient. A small set of basic assumptions leads to a consistent theoretical framework that is compatible with existing transport and compressibility measurements, and allows to make predictions for other observables. We also discuss connections between these ideas and other theories of transitions to an incompressible quantum fluid. 
D. Belitz and T.R. Kirkpatrick
cond-mat.str-el