Valentin AssassiDaniel BaumannDaniel Green2024-02-022024-02-022012-10-301029-8479https://scholars.lib.ntu.edu.tw/handle/123456789/63958031 pages, 1 figure; v2: references added + pedagogical improvements of Sec. 4In this paper, we prove that the superhorizon conservation of the curvature perturbation zeta in single-field inflation holds as an operator statement. This implies that all zeta-correlators are time independent at all orders in the loop expansion. Our result follows directly from locality and diffeomorphism invariance of the underlying theory. We also explore the relationship between the conservation of zeta, the single-field consistency relation and the renormalization of composite operators.Cosmology of Theories beyond the SM | Renormalization Regularization and Renormalons | Space-Time Symmetries; High Energy Physics - Theory; High Energy Physics - Theory; astro-ph.CO; High Energy Physics - Phenomenology[SDGs]SDG15journal article10.1007/JHEP02(2013)1512-s2.0-84876379610http://arxiv.org/abs/1210.7792v2