Conformal Anomaly and Scaling Dimensions of theO(n)Model from an Exact Solution on the Honeycomb Lattice

Abstract
The critical O(n) model on a finite honeycomb lattice is solved by the Bethe-Ansatz method. Amplitudes of the dominant finite-size corrections to part of the eigenspectrum are obtained analytically. A comparison with Cardy's predictions from the theory of conformal invariance leads to the exact results for the conformal anomaly and scaling dimensions.