Okay guys so I the lagrangian(adsbygoogle = window.adsbygoogle || []).push({});

[itex]\mathcal{L}=\dfrac{1}{2}\left( \partial_{\mu}\phi\partial^{\mu}\phi-m^{2}\phi^{2} \right)+\dfrac{\lambda}{4!}:\phi(x)^{4}:[/itex]

where [itex]\phi(x)[/itex] is a real scalar field.

I want to know how you can draw the self-energy diagrams at order [itex]\lambda[/itex] and [itex]\lambda^{2}[/itex] for a 2 => 2 scattering system. How do you go about doing this just by looking at the Lagrangian?

Thanks guys....

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# How to draw self-energy diagrams in phi^4 theory

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