QCD and e+e−→ baryon + antibaryon

We discuss the QCD constraints on e+e−→ baryon–antibaryon close to threshold, in light of the puzzling experimental data which indicate that close to threshold σ(e+e−→nn̄)>σ(e+e−→pp̄). We focus on the process e+e−→ΔΔ̄, which is particularly simple from the theoretical point of view. In this case it is possible to make exact QCD predictions for the relative yields of the four members of the Δ multiplet, modulo one crucial dynamical assumption.