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arXiv · hep-lat/0011055

Computer Simulations of 3d Lorentzian Quantum Gravity

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

We investigate the phase diagram of non-perturbative three-dimensional Lorentzian quantum gravity with the help of Monte Carlo simulations. The system has a first-order phase transition at a critical value $k_0^c$ of the bare inverse gravitational coupling constant $k_0$. For $k_0 > k_0^c$ the system reduces to a product of uncorrelated Euclidean 2d gravity models and has no intrinsic interest as a model of 3d gravity. For $k_0 < k_0^c$, extended three-dimensional geometries dominate the functional integral despite the fact that we perform a sum over geometries and no particular background is distinguished at the outset. Furthermore, all systems with $k_0 < k_0^c$ have the same continuum limit. A different choice of $k_0$ corresponds merely to a redefinition of the overall length scale.

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J. Ambjorn, J. Jurkiewicz, R. Loll. 2000-11-15. Computer Simulations of 3d Lorentzian Quantum Gravity. https://doi.org/10.1016/s0920-5632(01)00878-7

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