Representation transformation in quantum cosmology

Summary. -- The requirement that physical states be independent of the choice of configuration or momentum representation is regarded as a necessary condition satisficd by physical states of the Universe. This condition is used to rule out unphysical ones from the mathematically general solutions of quantum Hamiltonian constraint equations for the vacuum and non-vacuum closed Robertson-Walker space-times ~4thout cosmological constant. PACS 98.80.Hw - Mathematical and relativistic aspects of cosmology; quantum cosmology.