ar X iv : h ep - p h / 03 06 12 2 v 1 1 3 Ju n 20 03 On the precision of the theoretical predictions for ππ scattering June 13 , 2003

In a recent paper, Peláez and Ynduráin evaluate some of the low energy observables of ππ scattering and obtain flat disagreement with our earlier results. The authors work with unsubtracted dispersion relations, so that their results are very sensitive to the poorly known high energy behaviour of the scattering amplitude. Indeed, their calculations mainly illustrate the fact that the most important parameters in the low energy domain are the subtraction constants. We repeat their calculations on the basis of the standard, subtracted fixed-t dispersion relations. The outcome fully confirms our earlier findings.