LSS constraints with controlled theoretical uncertainties

TL;DR

This paper investigates how theoretical uncertainties in perturbative models impact cosmological constraints, emphasizing the importance of including these errors for realistic results, especially in galaxy surveys.

Contribution

It provides a consistent framework for incorporating theoretical errors into cosmological analyses, highlighting their significance for neutrino mass and non-Gaussianity constraints.

Findings

Galaxy surveys can detect minimal neutrino mass and local non-Gaussianity.

Improving equilateral non-Gaussianity constraints beyond CMB limits is challenging.

Including theoretical errors is essential for realistic cosmological parameter estimation.

Abstract

Forecasts and analyses of cosmological observations often rely on the assumption of a perfect theoretical model over a defined range of scales. We explore how model uncertainties and nuisance parameters in perturbative models of the matter and galaxy spectra affect constraints on neutrino mass and primordial non-Gaussianities. We provide a consistent treatment of theoretical errors and argue that their inclusion is a necessary step to obtain realistic cosmological constraints. We find that galaxy surveys up to high redshifts will allow a detection of the minimal neutrino mass and local non-Gaussianity of order unity, but improving the constraints on equilateral non-Gaussianity beyond the CMB limits will be challenging. We argue that similar considerations apply to analyses where theoretical models are based on simulations.