  This monograph introduces an exact model for a critical spin chain with
arbitrary spin S, which includes the Haldane--Shastry model as the special case
S=1/2. While spinons in the Haldane--Shastry model obey abelian half-fermi
statistics, the spinons in the general model introduced here obey non-abelian
statistics. This manifests itself through topological choices for the
fractional momentum spacings. The general model is derived by mapping exact
models of quantized Hall states onto spin chains. The book begins with
pedagogical review of all the relevant models including the non-abelian
statistics in the Pfaffian Hall state, and is understandable to every student
with a graduate course in quantum mechanics.
