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arXiv · 2502.12112

Role of the counterterms in the conservation of superhorizon curvature perturbations at one loop

Keisuke Inomata
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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 ultra-slow-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.

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Keisuke Inomata. 2025-02-17. Role of the counterterms in the conservation of superhorizon curvature perturbations at one loop. https://doi.org/10.1103/r8bh-s48f

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