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arXiv · 2009.05111

The phase diagram of the multi-matrix model with ABAB-interaction from functional renormalization

Astrid Eichhorn·Antonio D. Pereira·Andreas G. A. Pithis
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Abstract

At criticality, discrete quantum-gravity models are expected to give rise to continuum spacetime. Recent progress has established the functional renormalization group method in the context of such models as a practical tool to study their critical properties and to chart their phase diagrams. Here, we apply these techniques to the multi-matrix model with $ABAB$-interaction potentially relevant for Lorentzian quantum gravity in 3 dimensions. We characterize the fixed-point structure and phase diagram of this model, paving the way for functional RG studies of more general multi-matrix or tensor models encoding causality and subjecting the technique to another strong test of its performance in discrete quantum gravity by comparing to known results.

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Astrid Eichhorn, Antonio D. Pereira, Andreas G. A. Pithis. 2020-09-10. The phase diagram of the multi-matrix model with ABAB-interaction from functional renormalization. https://doi.org/10.1007/jhep12(2020)131

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