Light-quark vacuum condensates in chiral perturbation theory and QCD sum rules

The (simplified) relation (〈uu〉 - 〈dd〉)/(〈uu〉 - 〈ss〉) = (md- mu)/(ms-mu), originally obtained in chiral perturbation theory, relating light quark masses and condensates is rederived in the context of QCD or SVZ sum rules, thus establishing a non-trivial connection between the role played by meson resonances in these two QCD-inspired approaches. Accurate values for light quark condensates deduced from scalar QCD sum rules are also presented. © 1988.