By combining symmetry with the Bethe-ansatz solution of the one-dimensional Hubbard model with periodic boundary conditions a dynamical theory for the evaluation of one- and two-particle spectral functions is constructed. It involves the introduction of suitable quantum objects whose occupancy configurations generate the exact energy eigenstates associated with the Bethe-ansatz solution. Due to the integrability of the model, such objects have zero-momentum forward scattering only. The spectral properties are controlled by their phase shifts. Applications of the dynamical theory are shortly discussed. |