Theoretical foundation for treating decays allowed by the Okubo-Zweig-Iizuka rule and related phenomena

Abstract
We derive an expression for the width of unstable mesons whose decays are allowed by the Okubo-Zweig-Iizuka rule. The starting point is an exact expression. In the lattice version a strong-coupling and hopping-parameter expansion of it yields the specific nonperturbative factor for particle-antiparticle creation in a strong field. A more general treatment leads to an expression for the width involving only one universal constant independent of flavor and state. The relation of our formulation to earlier phenomenological approaches is discussed.