## Abstract

The relation between loop quantum gravity and Regge calculus has been pointed out many times in the literature. In particular the large spin asymptotics of the Barrett-Crane vertex amplitude is known to be related to the Regge action. In this paper we study a semiclassical regime of loop quantum gravity and show that it admits an effective description in terms of perturbative area-Regge-calculus. The regime of interest is identified by a class of states given by superpositions of four-valent spin networks, peaked on large spins. As a probe of the dynamics in this regime, we compute explicitly two- and three-area correlation functions at the vertex amplitude level. We find that they match with the ones computed perturbatively in area-Regge-calculus with a single 4-simplex, once a specific perturbative action and measure have been chosen in the Regge-calculus path integral. Correlations of other geometric operators and the existence of this regime for other models for the dynamics are briefly discussed.

Original language | English (US) |
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Pages (from-to) | 581-621 |

Number of pages | 41 |

Journal | Nuclear Physics B |

Volume | 796 |

Issue number | 3 |

DOIs | |

State | Published - Jun 21 2008 |

## All Science Journal Classification (ASJC) codes

- Nuclear and High Energy Physics