File(s) not publicly available
Moment transport equations for non-Gaussianity
journal contributionposted on 2023-06-07, 19:27 authored by David J Mulryne, David SeeryDavid Seery, Daniel Wesley
We present a novel method for calculating the primordial non-Gaussianity produced by super-horizon evolution during inflation. Our method evolves the distribution of coarse-grained inflationary field values using a transport equation. We present simple evolution equations for the moments of this distribution, such as the variance and skewness. This method possesses some advantages over existing techniques. Among them, it cleanly separates multiple sources of primordial non-Gaussianity, and is computationally efficient when compared with popular alternatives, such as the dN framework. We adduce numerical calculations demonstrating that our new method offers good agreement with those already in the literature. We focus on two fields and the f nl parameter, but we expect our method will generalize to multiple scalar fields and to moments of arbitrarily high order. We present our expressions in a field-space covariant form which we postulate to be valid for any number of fields.
JournalJournal of Cosmology and Astroparticle Physics
Department affiliated with
- Physics and Astronomy Publications
NotesAuthor list in alphabetical order.
Full text available