The perturbative Regge-calculus regime of loop quantum gravity

Eugenio Bianchi, Leonardo Modesto

Research output: Contribution to journalArticle

21 Citations (Scopus)

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 languageEnglish (US)
Pages (from-to)581-621
Number of pages41
JournalNuclear Physics B
Volume796
Issue number3
DOIs
StatePublished - Jun 21 2008

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calculus
gravitation
apexes
cranes
operators
probes

All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics

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Bianchi, Eugenio ; Modesto, Leonardo. / The perturbative Regge-calculus regime of loop quantum gravity. In: Nuclear Physics B. 2008 ; Vol. 796, No. 3. pp. 581-621.
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The perturbative Regge-calculus regime of loop quantum gravity. / Bianchi, Eugenio; Modesto, Leonardo.

In: Nuclear Physics B, Vol. 796, No. 3, 21.06.2008, p. 581-621.

Research output: Contribution to journalArticle

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AU - Modesto, Leonardo

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