Homework Statement
For a real scalar field \phi, the propagator is \frac{i}{(k^2-m_\phi^2)}.
If we instead assume a complex scalar field, \phi = \frac{1}{\sqrt{2}} (\phi_1 + i \phi_2), where \phi_1,\phi_2 are real fields with masses m_{\phi 1},m_{\phi 2}, what is the propagator...