4d models of dS uplift in KKLT

TL;DR

This paper critically examines various 4d KKLT models for de Sitter uplift, identifies inconsistencies in previous modifications, and constructs improved, fully consistent models that support the existence of dS vacua across a broad parameter range.

Contribution

The authors develop new, consistent 4d KKLT models with nilpotent superfields that confirm the existence of de Sitter vacua, resolving issues in earlier proposals.

Findings

Previous models have regions where |D_SW|^2 is negative or vanishes.

Improved models are consistent for all parameter values.

Existence of dS vacua is confirmed in the KKLT scenario.

Abstract

It was shown in arXiv:1808.09428 that the modified 4d version of the KKLT model proposed in arXiv:1707.08678 is inconsistent for large values of the parameter $c$ advocated in arXiv:1707.08678, since there is a point in the moduli space where $|D_SW|^2$ vanishes. The authors responded with yet another modification of the 4d KKLT model arXiv:1809.06618. However, for large $c$, this model suffers from an even worse problem: not only is there a point in the moduli space where $|D_SW|^2$ vanishes, there is also a region in the moduli space where $|D_SW|^2$ is negative. Meanwhile for small $c$ these models have dS vacua. We construct improved models, which are fully consistent for all values of parameters, just as the original version of the KKLT model using a nilpotent superfield. These models have a family of dS vacua for a broad range of parameter values. Thus, the results of the analysis of all presently available consistent generalizations of the 4d KKLT model, in the domain of their validity, confirm the existence of dS vacua in the KKLT scenario.