Abstract
One-dimensional critical quantum sytems have a universal, intensive ‘‘ground-state degeneracy,’’ g, which depends on the universality class of the boundary conditions, and is in general noninteger. This is calculated, using the conjectured boundary conditions corresponding to a multichannel Kondo impurity and shown to agree with Bethe-ansatz results. g is argued to decrease under renormalization from a less stable to a more stable critical point and plays a role in boundary critical phenomena quite analogous to that played by c, the conformal anomaly, in the bulk case.
- Received 3 April 1991
DOI:https://doi.org/10.1103/PhysRevLett.67.161
©1991 American Physical Society