CP(N-1) model on finite interval in the large N limit
  The CP(N-1) \sigma\ model on finite interval of length R with Dirichlet boundary conditions is analysed in the 1/N expansion. The theory has two phases, separated by a phase transition at R ~ 1/\Lambda, \Lambda\ is dynamical scale of the CP(N-1) model. The vacuum energy dependence of R, and especially Casimir-type scaling 1/R, is discussed. 
A. Milekhin
hep-th