Alessio Baldazzi: Essential renormalization group

We use the generalised flow of the Effective average action which incorporates field redefinitions along the RG flow. This equation allows for the implementation of essential schemes, i.e. schemes where one can fix the value of inessential couplings. From the practical point of view, this produces simplifications in practical calculations, while from the conceptual point of view it provides a clearer picture of renormalisation itself since the redundant, non-physical content can be automatically disregarded in favor of a description based only on quantities that enter expressions for physical observables. To exemplify the scheme’s utility, we investigate the Wilson-Fisher fixed point in three dimensions at order two in the derivative expansion. Finally, we comment on the implications for the Asymptotic safety programme.