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arXiv · 1905.06963

Duality Invariant Cosmology to all Orders in $\alpha'$

Olaf Hohm·Barton Zwiebach
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Abstract

While the classification of $\alpha'$ corrections of string inspired effective theories remains an unsolved problem, we show how to classify duality invariant $\alpha'$ corrections for purely time-dependent (cosmological) backgrounds. We determine the most general duality invariant theory to all orders in $\alpha'$ for the metric, $b$-field, and dilaton. The resulting Friedmann equations are studied when the spatial metric is a time-dependent scale factor times the Euclidean metric and the $b$-field vanishes. These equations can be integrated perturbatively to any order in $\alpha'$. We construct non-perturbative solutions and display duality invariant theories featuring string-frame de Sitter vacua.

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Olaf Hohm, Barton Zwiebach. 2019-05-16. Duality Invariant Cosmology to all Orders in $\alpha'$. https://doi.org/10.1103/physrevd.100.126011

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