Free Variables and the Two Matrix Model
  We study the full set of planar Green's functions for a two-matrix model using the language of functions of non-commuting variables. Both the standard Schwinger-Dyson equations and equations determining connected Green's functions can be efficiently discussed and solved. This solution determines the master field for the model in the `$C$-representation.' 
M. R. Douglas (Rutgers University) and M. Li (Brown University)