Tetraquarks: relativistic corrections and other issues

Abstract

We discuss the effect of relativistic kinematics on the binding energy of multiquark states. For a given potential, the use of relativistic kinematics lowers the energy by a larger amount for the threshold made of two mesons than for a tetraquark, so that its binding is weakened. Some other issues associated with exotic hadrons are also briefly discussed.

Comments: 7 pages, 2 figures, Contribution to Hadron 2021 (19th International Conference on Hadron Spectroscopy and Structure in memoriam Simon Eidelman), Mexico City, 26-31 July 2021, to appear in the Proceedings (Suplemento de la Revista Mexicana de Fisica). Version 2: changes in the format of bibliography