Charge conjugation invariance of the Spectator Equations

Abstract

In response to recent critcism, we show how to define the spectator equations for negative energies so that charge conjugation invariance is preserved. The result, which emerges naturally from the application of spectator principles to systems of particles with negative energies, is to replace all factors of the external energies $W_i$ by $\sqrt{W^2_i}$, insuring that the amplitudes are independent of the sign of the energies $W_i$.