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arXiv · gr-qc/9605017

Inflationary and Deflationary Branches in Extended Pre--Big Bang Cosmology

James E. Lidsey
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Abstract

The pre--big bang cosmological scenario is studied within the context of the Brans--Dicke theory of gravity. An epoch of superinflationary expansion may occur in the pre--big bang phase of the Universe's history in a certain region of parameter space. Two models are considered that contain a cosmological constant in the gravitational and matter sectors of the theory, respectively. Classical pre-- and post--big bang solutions are found for both models. The existence of a curvature singularity forbids a classical transition between the two branches. On the other hand, a quantum cosmological approach based on the tunneling boundary condition results in a non--zero transition probability. The transition may be interpreted as a spatial reflection of the wavefunction in minisuperspace.

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James E. Lidsey. 1996-05-08. Inflationary and Deflationary Branches in Extended Pre--Big Bang Cosmology. https://doi.org/10.1103/physrevd.55.3303

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