Recent content by karlsson

You are right. Thanks a lot.

Sry, I don't understand. My solution is a different one as from Peskin & Schroeder. But why?

I hope this is the correct place for my question. I posted it here, because it`s from Peskin & Schroeder: "Consider the amplitude for a free particle to propagate from \mathbf{x}_{0} to \mathbf{x} : U(t)=\left\langle \mathbf{x}\right|e^{-iHt}\left|\mathbf{x_{0}}\right\rangle In...