I. THEORY OF STRONGLY CORRELATED ELECTRON

1. Exact thermodynamics and dynamics in one-dimensional models Exact thermodynamics is constructed for the one-dimensional supersymmet-ric t-J model with the 1 / sin2 interaction and hopping. The result is described exactly in terms of free spinons and holons obeying Haldane’s fractional exclusion statistics at all temperatures [1]. Explicit results for the spin and charge suscep-tibilities, and specific heat are obtained, which are interpreted in terms of the fractional exclusion statistics. The extention to the multi-component t-J model shows that the excitations under magnetic field obey fractional statistics, and without magnetic field the parafermionic one. We have reviewed the status of the subject in a workshop [2]. The extension of the model to include anisotropy in the exchange interaction and the hopping is achieved [3]. The extended model has a unique feature that it has an analytically solvable subspace, but is not com-pletely integrable. The overlap between the exact solution numerically obtained and the Jastrow-type trial function is surprisingly close to unity for all values o