Fundamental Physics from Future Spectroscopic Surveys

Non-perturbative techniques for constraining the cosmological collider

7 May 2024, 11:30

10m

Auditorium (Building 50)

Session 6

Speaker

Samuel Goldstein (Columbia University)

Description

Upcoming large-scale structure (LSS) surveys will provide significant insight into the physics of the early Universe by searching for primordial non-Gaussianity (PNG). Whereas traditional approaches towards constraining PNG with LSS typically focus on phenomenological amplitudes, e.g., $f_{\mathrm{N}\mathrm{L}}^{\mathrm{l}\mathrm{o}\mathrm{c}.}$, which characterize a given "shape" of non-Gaussianity, there exist a range of inflationary scenarios that can produce unique signatures of PNG. A particularly compelling example is the cosmological collider scenario, wherein the presence of massive spinning particles during inflation can lead to poles or oscillations in the squeezed bispectrum. In this talk, I will present a novel approach towards running and analyzing N-body simulations with initial conditions generated for cosmological collider type models. Using these simulations, I will validate a model for the non-linear squeezed matter bispectrum and collapsed trispectrum for the collider physics scenario based on the LSS consistency relations -- non-perturbative statements about the structure of LSS correlation functions derived from symmetries of the LSS equations of motion. Finally, I will comment on how these simulations and non-perturbative models can be used to develop pipelines to directly constrain the masses and spins of particles present during inflation.

Presentation materials

LBL_SpecV_conference.pdf