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Maximally Symmetric Cosmological Solutions of Type II Superstrings

M. C. Bento
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Abstract

We study maximally symmetric cosmological solutions of type II supersymmetric strings in the presence of the exact, SL(2,Z)-invariant, higher-curvature corrections to the lowest order effective action. We find that, unlike the case of type IIA theories, de Sitter solutions exist, at all orders in $α'$, for type IIB superstrings, when non-perturbative instanton-effects are included on the basis of SL(2,Z) invariance.

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M. C. Bento. 1999-02-19. Maximally Symmetric Cosmological Solutions of Type II Superstrings. https://arxiv.org/abs/gr-qc/9902058

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