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luisgml_2000
Oct8-09, 01:35 AM
Hello.

I've been given a certain lagrangian density \mathcal{L}(\phi,\phi^*,\frac{\partial \phi}{\partial x},\frac{\partial \phi^*}{\partial x}) and I'm asked to obtain the Lagrange equations of motion.

My question is this: is the variation of \phi^* and that of its derivative independent of the variations of \phi and its derivative? Will I get one or two partial differential equations?

Thanks for your attention.