Tensors, non-Gaussianities, and the future of potential reconstruction

TL;DR

This paper analyzes how tensor perturbations and non-Gaussianities influence the reconstruction of the inflationary potential using simulated Planck data, highlighting the importance of detecting both for accurate constraints.

Contribution

It provides a detailed forecast of potential constraints on inflationary models considering non-Gaussianities and tensors, using MCMC and flow analyses on simulated data.

Findings

Failure to detect non-Gaussianities hampers potential reconstruction.

Non-detection of tensors prevents determining the inflation energy scale.

Detecting both tensors and non-Gaussianities yields optimal constraints.

Abstract

We present projections for reconstruction of the inflationary potential expected from ESA's upcoming Planck Surveyor CMB mission. We focus on the effects that tensor perturbations and the presence of non-Gaussianities have on reconstruction efforts in the context of non-canonical inflation models. We consider potential constraints for different combinations of detection/null-detection of tensors and non-Gaussianities. We perform Markov Chain Monte Carlo and flow analyses on a simulated Planck-precision data set to obtain constraints. We find that a failure to detect non-Gaussianities precludes a successful inversion of the primordial power spectrum, greatly affecting uncertainties, even in the presence of a tensor detection. In the absence of a tensor detection, while unable to determine the energy scale of inflation, an observable level of non-Gaussianities provides correlations between the errors of the potential parameters, suggesting that constraints might be improved for suitable combinations of parameters. Constraints are optimized for a positive detection of both tensors and non-Gaussianities.