Finite Size Effects and Scaling in Lattice CP N − 1

We present model predictions for the spectrum of CP N −1 in a periodic box and use them to interpret the strong finite size effects observed in lattice simulations at medium values of N. The asymptotic scaling behaviour of alternative lattice actions is discussed along with some aspects of multigrid algorithm efficiency. Introduction There has been considerable recent interest in simulations of the lattice CP N −1 model [1, 2, 3, 4, 5]. Advances in the development of non-local Monte Carlo algorithms have given added impetus to studies of the model at large N where the spectrum remains unconfirmed by analytic or numerical analysis. Conflicting evidence has been presented for perturbative (two-loop) scaling at currently accessible values of the bare coupling.