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arXiv · hep-th/9602087

Graceful exit in quantum string cosmology

M. Gasperini·J. Maharana·G. Veneziano
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Abstract

We write an O(d,d)-covariant Wheeler-De Witt equation in the ($d^2+1$)-dimensional minisuperspace of low-energy cosmological string backgrounds. We discuss explicit examples of transitions between two duality-related cosmological phases, and we find a finite quantum transition probability even when the two phases are classically separated by a curvature singularity. This quantum approach is completely free from operator ordering ambiguities as a consequence of the duality symmetries of the string effective action.

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M. Gasperini, J. Maharana, G. Veneziano. 1996-02-16. Graceful exit in quantum string cosmology. https://doi.org/10.1016/0550-3213(96)00201-5

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