What binds quarks together at different momentum scales? A conceptual scenario

The binding effects of quarks within hadrons are discussed in terms of the pion distribution amplitude over longitudinal momentum fractions. To understand the behavior of this quantity at different momentum scales, the concept of synchronization in complex systems has been employed. It is argued that at low momentum scales, the quarks get correlated by nonlocal quark/gluon condensates that cause an endpoint-suppressed, mainly bimodal structure of the pion distribution amplitude inferred from a sum-rule analysis. The mass generation mechanism, within the framework of Dyson-Schwinger equations, and evolution effects pull these two peaks back to the center to form at $Q^2\to\infty$ the asymptotic distribution amplitude which represents the most synchronized $\bar{q}q$ state.Comment: 5 pages, 3 figures embedded; v2 includes remarks on and references to AdS/QCD; v3 has 6 pages, new material on short-tailed platykurtic distribution amplitude and minor corrections and clarifications added; abstract extended and references update