Speaker
Description
Primordial non-Gaussianity is one of the most important signals for probing the physics of the early universe. Over the past decade, constraints on primordial non-Gaussianity (quantified by the parameter fNL) from the Planck experiment have ruled out a number of simple inflationary models. In the coming years, ongoing and upcoming large-scale structure (LSS) surveys (e.g., SPHEREx) will likely achieve constraints on non-Gaussianity several times tighter than Planck, enabling us to test or exclude a broad class of inflationary scenarios—particularly multi-field inflation.
However, current LSS analyses measuring fNL typically neglect the impact of non-Gaussianity in the covariance matrix, which could systematically bias the inferred central value and uncertainty of fNL. This work aims to investigate: Given current survey designs, at what level of fNLsensitivity does ignoring non-Gaussianity in the covariance matrix begin to significantly affect our constraints?
