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arXiv · hep-th/0412240

Cosmic Acceleration and the String Coupling

John Ellis·N. E. Mavromatos·D. V. Nanopoulos
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Abstract

In the context of a cosmological string model describing the propagation of strings in a time-dependent Robertson-Walker background space-time, we show that the asymptotic acceleration of the Universe can be identified with the square of the string coupling. This allows for a direct measurement of the ten-dimensional string coupling using cosmological data. We conjecture that this is a generic feature of a class of non-critical string models that approach asymptotically a conformal (critical) sigma model whose target space is a four-dimensional space-time with a dilaton background that is linear in sigma-model time. The relation between the cosmic acceleration and the string coupling does not apply in critical strings with constant dilaton fields in four dimensions.

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John Ellis, N. E. Mavromatos, D. V. Nanopoulos. 2004-12-20. Cosmic Acceleration and the String Coupling. https://doi.org/10.1016/j.physletb.2005.05.047

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