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arXiv · hep-th/0411152

Semiclassical Universe from First Principles

J. Ambjorn·J. Jurkiewicz·R. Loll
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Abstract

Causal Dynamical Triangulations in four dimensions provide a background-independent definition of the sum over space-time geometries in nonperturbative quantum gravity. We show that the macroscopic four-dimensional world which emerges in the Euclidean sector of this theory is a bounce which satisfies a semiclassical equation. After integrating out all degrees of freedom except for a global scale factor, we obtain the ground state wave function of the universe as a function of this scale factor.

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J. Ambjorn, J. Jurkiewicz, R. Loll. 2004-11-16. Semiclassical Universe from First Principles. https://doi.org/10.1016/j.physletb.2004.12.067

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