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arXiv · hep-th/0307263

Renormalization of 3d quantum gravity from matrix models

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

Lorentzian simplicial quantum gravity is a non-perturbatively defined theory of quantum gravity which predicts a positive cosmological constant. Since the approach is based on a sum over space-time histories, it is perturbatively non-renormalizable even in three dimensions. By mapping the three-dimensional theory to a two-matrix model with ABAB interaction we show that both the cosmological and the (perturbatively) non-renormalizable gravitational coupling constant undergo additive renormalizations consistent with canonical quantization.

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J. Ambjorn, J. Jurkiewicz, R. Loll. 2003-07-27. Renormalization of 3d quantum gravity from matrix models. https://doi.org/10.1016/j.physletb.2003.11.068

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