New non-perturbative de Sitter vacua in $\alpha'$-complete cosmology

TL;DR

This paper constructs and analyzes new non-perturbative de Sitter vacua within $ ext{O}(d,d)$ invariant $ ext{alpha'}$-complete string cosmology, revealing stable and unstable solutions with diverse geometries and fields, extending previous perturbative results.

Contribution

It introduces a systematic construction of non-perturbative de Sitter solutions in $ ext{alpha'}$-complete cosmology, including anisotropic and $b$-field configurations, expanding the landscape of string vacua.

Findings

Discovery of stable and unstable de Sitter solutions in string and Einstein frames.

Identification of new geometries like $d+1$-dimensional and $d+1$-dimensional with $T^{d-n}$ factors.

Solutions with bounded scale factors and non-trivial $b$-field configurations.

Abstract

The $\alpha'$-complete cosmology developed by Hohm and Zwiebach classifies the ${\rm O}(d,d;{\mathbb R})$ invariant theories involving metric, $b$-field and dilaton that only depend on time, to all orders in $\alpha'$. Some of these theories feature non-perturbative isotropic de Sitter vacua in the string frame, generated by the infinite number of higher-derivatives of ${\rm O}(d,d;{\mathbb R})$ multiplets. Extending the isotropic ansatz, we construct stable and unstable non-perturbative de Sitter solutions in the string and Einstein frames. The generalized equations of motion admit new solutions, including anisotropic $d+1$-dimensional metrics and non-vanishing $b$-field. In particular, we find dS$_{n+1}\times T^{d-n}$ geometries with constant dilaton, and also metrics with bounded scale factors in the spatial dimensions with non-trivial $b$-field. We discuss the stability and non-perturbative character of the solutions, as well as possible applications.