  A multi-channel algebraic scattering theory, to find solutions of
coupled-channel scattering problems with interactions determined by collective
models, has been structured to ensure that the Pauli principle is not violated.
Positive (scattering) and negative (sub-threshold) solutions can be found to
predict both the compound nucleus sub-threshold spectrum and all resonances due
to coupled-channel effects that occur on a smooth energy varying background.
The role of the Pauli principle is crucial in defining what interaction
potentials are required to fit data. The theory also gives an algebraic form
for the dynamic polarization potential which adds to the ground state
interaction to define the optical potential that gives the same elastic
scattering cross sections.
