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arXiv · hep-lat/0309002

Indications for Criticality at Zero Curvature in a 4d Regge Model of Euclidean Quantum Gravity

Wolfgang Beirl·Bernd A. Berg
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Abstract

We re-examine the approach to four-dimensional Euclidean quantum gravity based on the Regge calculus. A cut-off on the link lengths is introduced and consequently the gravitational coupling and the cosmological constant become independent parameters. We determine the zero curvature, $ =0$, line in the coupling constant plane by numerical simulations. When crossing this line we find a strong, probably first order, phase transition line with indications of a second order endpoint. Beyond the endpoint the transition through the $ =0$ line appears to be a crossover. Previous investigations, using the Regge or the Dynamical Triangulation approach, dealt with a limit in which the first order transition prevails.

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Wolfgang Beirl, Bernd A. Berg. 2003-08-30. Indications for Criticality at Zero Curvature in a 4d Regge Model of Euclidean Quantum Gravity. https://doi.org/10.1016/s0920-5632(03)02718-x

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