Physical solution of 1D quantum N-boson system with zero-range pair interaction

The mathematically exact solution of a one-dimensional (1D) quantum N-identical-boson system with zero-range pair interaction has been well known. We find that this solution is non-physical, since there exists a paradox of its energy expectation value, leading a basic contradiction to the mean-field theory of the system. A new integral equation that is equivalent to the corresponding Schrodinger one is established and its formally physical solution is derived. Energy correction from the average potential and harmonic waves of different momentums are demonstrated, and scattering amplitude of the physical solution and mean-field theory of the system are discussed.