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arXiv · 1811.00814

Towards background independent quantum gravity with tensor models

Astrid Eichhorn·Tim Koslowski·Johannes Lumma·Antonio D. Pereira
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Abstract

We explore whether the phase diagram of tensor models could feature a pregeometric, discrete and a geometric, continuum phase for the building blocks of space. The latter are associated to rank $d$ tensors of size $N$. We search for a universal large $N$ scaling limit in a rank-3 model with real tensors that could be linked to a transition between the two phases. We extend the conceptual development and practical implementation of the flow equation for the pregeometric setting. This provides a pregeometric "coarse-graining" by going from many microscopic to few effective degrees of freedom by lowering $N$. We discover several candidates for fixed points of this coarse graining procedure, and specifically explore the impact of a novel class of interactions allowed in the real rank-3 model. In particular, we explain how most universality classes feature dimensional reduction, while one candidate, involving a tetrahedral interaction, might potentially be of relevance for three-dimensional quantum gravity.

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Astrid Eichhorn, Tim Koslowski, Johannes Lumma, Antonio D. Pereira. 2018-11-02. Towards background independent quantum gravity with tensor models. https://doi.org/10.1088/1361-6382%2Fab2545

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