Testing Inflation with Dark Matter Halos

TL;DR

This paper explores how primordial non-Gaussianity from inflationary models affects large-scale structure, comparing analytic and N-body simulations to improve constraints on early universe physics.

Contribution

It models the effects of specific non-Gaussianity types on halo clustering and mass function, comparing analytic and N-body results for curvaton inflation variants.

Findings

Analytic and N-body results show consistent effects of non-Gaussianity on halo clustering.

Different curvaton models produce distinguishable signatures in large-scale structure.

Results improve understanding of how inflationary physics influences observable cosmic structures.

Abstract

Cosmic inflation provides a mechanism for generating the early density perturbations that seeded the large-scale structures we see today. Primordial non-Gaussianity is among the most promising of few observational tests of physics at this epoch. At present non-Gaussianity is best constrained by the cosmic microwave background, but in the near term large-scale structure data may be competitive so long as the effects of primordial non-Gaussianity can be modeled through the non-linear process of structure formation. We discuss recent work modeling effects of a few types of primordial non-Gaussianity on the large-scale halo clustering and the halo mass function. More specifically, we compare analytic and N-body results for two variants of the curvaton model of inflation: (i) a "tauNL" scenario in which the curvaton and inflaton contribute equally to the primordial curvature perturbation and (ii) a "gNL" model where the usual quadratic fNL term in the potential cancels, but a large cubic term remains.