What is the Operator Product Expansion in Interacting Field Theory?

[gullio]

hello,
I'm trying to find a good and exaustive explanation of operator product expansion.
I've read "renormalization" and weinberg but i continue to not understand ope in interacting field theory.
someone could help me?

 

[Ben Niehoff]

Do you have a specific question? Also, have you read the big yellow book (Francesco)?

 

[gullio]

Yes but explain only conformal field theory.
For example I'm not able to wright down the ope for \lamda \phi^4. I don't know how to start

 

[Ben Niehoff]

Sorry, I don't know anything about OPEs for non-conformal theories.