Assassi, ValentinValentinAssassiDaniel BaumannGreen, DanielDanielGreen2024-02-022024-02-022012-11-011475-7516https://scholars.lib.ntu.edu.tw/handle/123456789/639581Soft limits of inflationary correlation functions are both observationally relevant and theoretically robust. Various theorems can be proven about them that are insensitive to detailed model-building assumptions. In this paper, we re-derive several of these theorems in a universal way. Our method makes manifest why soft limits are such an interesting probe of the spectrum of additional light fields during inflation. We illustrate these abstract results with a detailed case study of the soft limits of quasi-single-field inflation. © 2012 IOP Publishing Ltd and Sissa Medialab srl.inflation | non-gaussianity[SDGs]SDG8journal article10.1088/1475-7516/2012/11/0472-s2.0-84870286642https://api.elsevier.com/content/abstract/scopus_id/84870286642