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arXiv · hep-th/0504011

Cosmological D-instantons and Cyclic Universes

E. A. Bergshoeff·A. Collinucci·D. Roest·J. G. Russo·P. K. Townsend
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Abstract

For models of gravity coupled to hyperbolic sigma models, such as the metric-scalar sector of IIB supergravity, we show how smooth trajectories in the `augmented target space' connect FLRW cosmologies to non-extremal D-instantons through a cosmological singularity. In particular, we find closed cyclic universes that undergo an endless sequence of big-bang to big-crunch cycles separated by instanton `phases'. We also find `big-bounce' universes in which a collapsing closed universe bounces off its cosmological singularity to become an open expanding universe.

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E. A. Bergshoeff, A. Collinucci, D. Roest, J. G. Russo, P. K. Townsend. 2005-04-23. Cosmological D-instantons and Cyclic Universes. https://doi.org/10.1088/0264-9381%2F22%2F13%2F008

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