HOW RELIABLY CAN HADRONIC DISTRIBUTION AMPLITUDES BE RECONSTRUCTED FROM QCD SUM-RULES

We examine the problem of how accurately hadronic distribution amplitu des can be reconstructed from given sum rule moments. It is found that the expansion coefficients of wave functions are uniquely determined by the moments, but additionally are highly sensitive to small changes in the moments. As a consequence, the inherent uncertainty in such mo ments leads to a considerable indefiniteness of the wave functions. Th us, it seems that the widely used procedure of constructing wave funct ions from QCD sum rule moments becomes questionable.