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arXiv · hep-th/0505154

Reconstructing the Universe

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

We provide detailed evidence for the claim that nonperturbative quantum gravity, defined through state sums of causal triangulated geometries, possesses a large-scale limit in which the dimension of spacetime is four and the dynamics of the volume of the universe behaves semiclassically. This is a first step in reconstructing the universe from a dynamical principle at the Planck scale, and at the same time provides a nontrivial consistency check of the method of causal dynamical triangulations. A closer look at the quantum geometry reveals a number of highly nonclassical aspects, including a dynamical reduction of spacetime to two dimensions on short scales and a fractal structure of slices of constant time.

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J. Ambjorn, J. Jurkiewicz, R. Loll. 2005-06-06. Reconstructing the Universe. https://doi.org/10.1103/physrevd.72.064014

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