Role of the counterterms in the conservation of superhorizon curvature perturbations at one loop
Phys. Rev. D 111, 123517 – Published 11 June, 2025
DOI: https://doi.org/10.1103/r8bh-s48f
Abstract
Recently, several papers have claimed that superhorizon curvature perturbations are not conserved at the one-loop level in single-field inflation models if there is a transient ultraslow-roll period. In this work, we point out that the contributions from the counterterms were overlooked in the recent papers. We show that the counterterm contributions play a crucial role in canceling the one-loop power spectrum of superhorizon curvature perturbations in the comoving gauge.
