Chapter 9
Mass inequalities

In this chapter, we first discuss the mass dependence of the three-body binding energy and derive inequalities linking baryons of different flavour content. Then we present inequalities relating the binding energies of baryons to those of simpler two-body systems, which can, to some extent, be identified as mesons. The rough inequalities by Ader et al.and Nussinov [8384] have been significantly improved recently [8586], so that the lower bounds now become rather accurate approximations of the three-body binding energies in terms of two-body binding energies.

 9.1 Mass dependence of the three-body binding energy
 9.2 Relation between the quark–antiquark and the quark–quark potentials
 9.3 Simple lower bound on baryon energies
 9.4 Improved lower bounds
 9.5 Comparison of the wave functions
 9.6 Connection to physical mesons
 9.7 The case of unequal constituent masses
 9.8 Generalization to excited states