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A diagrammatic approach to calculate n-point correlators of the primordialcurvature perturbation \zeta was developed a few years ago following the spiritof the Feynman rules in Quantum Field Theory. The methodology is very usefuland time-saving, as it is for the case of the Feynman rules in the particlephysics context, but, unfortunately, is not very well known by the cosmologycommunity. In the present work, we extend such an approach in order to includenot only scalar field perturbations as the generators of \zeta, but also vectorfield perturbations. The purpose is twofold: first, we would like thediagrammatic approach (which we would call the Feynman-like rules) to becomewidespread among the cosmology community; second, we intend to give an easytool to formulate any correlator of \zeta for those cases that involve vectorfield perturbations and that, therefore, may generate prolonged stages ofanisotropic expansion and/or important levels of statistical anisotropy.Indeed, the usual way of formulating such correlators, using the Wick'stheorem, may become very clutter and time-consuming.

Feynman-like Rules for Calculating n-Point Correlators of the Primordial Curvature Perturbation