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arXiv · 2101.01070

Quantum string cosmology

M. Gasperini
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Abstract

We present a short review of possible applications of the Wheeler-De Witt equation to cosmological models based on the low-energy string effective action, and characterised by an initial regime of asymptotically flat, low energy, weak coupling evolution. Considering in particular a class of duality-related (but classically disconnected) background solutions, we shall discuss the possibility of quantum transitions between the phases of pre-big bang and post-big bang evolution. We will show that it is possible, in such a context, to represent the birth of our Universe as a quantum process of tunneling or "anti-tunneling" from an initial state asymptotically approaching the string perturbative vacuum.

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M. Gasperini. 2021-01-04. Quantum string cosmology. https://doi.org/10.3390/universe7010014

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