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arXiv · 2305.00222

Non-singular pre-big bang scenarios from all-order $\alpha'$ corrections

M. Gasperini·G. Veneziano
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Abstract

We reformulate in Hamiltonian language the recent proposal by Hohm and Zwiebach of an action yielding the most general $O(d,d)$-symmetric string cosmology equations, at tree-level in the string-loop expansion, but to all orders in the $\alpha'$ expansion. This allows us to give a simple characterization of a large class of non-singular, non-perturbative, pre-big bang scenarios smoothly interpolating between a low-energy initial accelerated (string frame) expansion and a phase of final (string and Einstein frame) decelerated expansion. Interestingly, these solutions must necessarily include, just around the bounce, a very short phase of (string-frame) contraction.

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M. Gasperini, G. Veneziano. 2023-04-27. Non-singular pre-big bang scenarios from all-order $\alpha'$ corrections. https://doi.org/10.1007/jhep07(2023)144

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