We study two-body correlations in a many-boson system with a hyperspherical
approach, where we can use arbitrary scattering length and include two-body
bound states. As a special application we look on Bose-Einstein condensation
and calculate the stability criterium in a comparison with the experimental
criterium and the theoretical criterium from the Gross-Pitaevskii equation.Comment: 6 pages, 4 figures. Contribution to Workshop on Critical Stability
III in Trento. Submitted to Few-Body System