Mind the gap

Abstract

In this summary of the application of Dyson-Schwinger equations to the theory and phenomenology of hadrons, some deductions following from a nonperturbative, symmetry-preserving truncation are highlighted, notable amongst which are results for pseudoscalar mesons. We also describe inferences from the gap equation relating to the radius of convergence of a chiral expansion, applications to heavy-light and heavy-heavy mesons, and quantitative estimates of the contribution of quark orbital angular momentum in pseudoscalar mesons; and recapitulate upon studies of nucleon electromagnetic form factors.

Comments: 7 pages, 3 figures. Contribution to Proceedings of 4th International Conference on Quarks and Nuclear Physics (QNP06), Madrid, Spain, 5-10 Jun 2006