2012/04/30 by Valentin Assassi, Daniel Baumann, Daniel Green · 1 citation
Physics and Astronomy · #astro-ph.CO #hep-ph #hep-th
paper · pdf · doi:10.1088/1475-7516/2012/11/047
26 pages, 5 figures; V2: references added + pedagogical improvements of Sec. 2 and App. A
arxiv created 2012/06/25 · arxiv updated 2015/06/04
Soft 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.