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arXiv · 2107.00053

General String Cosmologies at Order $α'{}^{\,3}$

Tomas Codina·Olaf Hohm·Diego Marques
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Abstract

We compute the cosmological reduction of general string theories, including bosonic, heterotic and type II string theory to order $α'^{3}$, i.e., with up to eight derivatives. To this end we refine recently introduced methods that allow one to bring the reduced theory in one dimension to a canonical form with only first-order time derivatives. The resulting theories are compatible with a continuous $O(d,d,\mathbb{R})$ invariance, which in turn fixes the B-field couplings.

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Tomas Codina, Olaf Hohm, Diego Marques. 2021-08-04. General String Cosmologies at Order $α'{}^{\,3}$. https://doi.org/10.1103/physrevd.104.106007

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