Field Redefinitions and Infinite Field Anomalous Dimensions

Field redefinitions are commonly used to reduce the number of operators in the Lagrangian by removing redundant operators and transforming to a minimal operator basis. We give a general argument that such field redefinitions, while leaving the $S$-matrix invariant and consequently finite, lead not only to infinite Green’s functions, but also to infinite field anomalous dimensions ${\gamma }_{\phi }$. These divergences cannot be removed by counterterms without reintroducing redundant operators.