Primordial non-Gaussianity and Bispectrum Measurements in the Cosmic Microwave Background and Large-Scale Structure

TL;DR

This paper reviews how bispectrum measurements in the CMB and large-scale structure serve as key probes for primordial non-Gaussianity, discussing current results, challenges, and future prospects in constraining inflationary models.

Contribution

It provides a comprehensive comparison of theoretical and observational approaches to bispectrum analysis, highlighting the potential for future constraints on primordial non-Gaussianity.

Findings

Current bispectrum measurements constrain non-Gaussian parameters.

Future observations are expected to improve detection sensitivity.

The bispectrum analysis links to specific inflationary model predictions.

Abstract

The most direct probe of non-Gaussian initial conditions has come from bispectrum measurements of temperature fluctuations in the Cosmic Microwave Background and of the matter and galaxy distribution at large scales. Such bispectrum estimators are expected to continue to provide the best constraints on the non-Gaussian parameters in future observations. We review and compare the theoretical and observational problems, current results and future prospects for the detection of a non-vanishing primordial component in the bispectrum of the Cosmic Microwave Background and large-scale structure, and the relation to specific predictions from different inflationary models.