# How can I define complex scalar field in Cadabra?

You don't need to do anything special for this, just use a \phi and perhaps give it a Depends property to make it implicitly depend on a coordinate or derivative. If that doesn't help, can you say a bit more about what you are trying to do?

I am trying to find the equation(s) of motion for a complex scalar field lagrangian. I have to define the complex conjugate of scalar field '\phi'. Defining '\phi = \chi + i \xi' and '\phi^* = \chi - i \xi' is not working.

So you have an action in terms of \phi and \phi^* and then want to substitute in terms of the real and imaginary components, and then vary with respect to those components? Or do you want to do it the physicists' way and vary with respect to \phi and \phi^* 'independently'?

yes, I want to vary it with respect to '\phi' and '\phi^'. I want 'phi' and 'phi^' to be complex conjugate so that my action should be real.