Non-gaussianity of inflationary field perturbations from the field equation
نویسندگان
چکیده
We calculate the tree-level bispectrum of the inflaton field perturbation directly from the field equations, and construct the corresponding fNL parameter. Our results agree with previous ones derived from the Lagrangian. We argue that quantum theory should only be used to calculate the correlators when they first become classical a few Hubble times after horizon exit, the classical evolution taking over thereafter.
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