Nonlinear Generalizations of the Klein Gordon Equation
•The field equations for spin-zero meson fields used in the derivation of SWEPs are nonlinear generalization of the well known  Klein-Gordon equation. They are of the form1:
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J is the meson filed self interaction current.
lI  (i=1…n)  are self interaction coupling constants.
1.Reference: P.B. Burt, Quantum
 Mechanics and Nonlinear Waves
( Harwood Academic, N.Y. 1981)
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