The spin-dependent terms of an approximate, Breit-Fermi-type Hamiltonian for heavy quark-antiquark pairs are obtained by the use of an effective-action approach to QCD statics. As an introduction, a review of the effective action method and the related confinement mechanism is given. The method is extended to include spin-spin effects and the spin-orbit terms are derived from the spin-spin potential in a natural way. The quantitative functional form of the spin potential is given in terms of the solutions to numerical problems that are formulated but not solved. The solution of these problems will be reported in a subsequent paper.
Bibliographical noteFunding Information:
The problem considered here was suggested by S. L. Adler and subsequent were quite helpful. The hospitality of Brookhaven National Laboratory during was also appreciated. This work was supported in part by an Albert Einstein established by the Federal Republic of Germany and in part by the Department DE-AC02-76E:R02220.
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