Semiclassical regime of Regge calculus and spin foams

Eugenio Bianchi, Alejandro Satz

Research output: Contribution to journalArticle

16 Citations (Scopus)

Abstract

Recent attempts to recover the graviton propagator from spin foam models involve the use of a boundary quantum state peaked on a classical geometry. The question arises whether beyond the case of a single simplex this suffices for peaking the interior geometry in a semiclassical configuration. In this paper we explore this issue in the context of quantum Regge calculus with a general triangulation. Via a stationary phase approximation, we show that the boundary state succeeds in peaking the interior in the appropriate configuration, and that boundary correlations can be computed order by order in an asymptotic expansion. Further, we show that if we replace at each simplex the exponential of the Regge action by its cosine-as expected from the semiclassical limit of spin foam models-then the contribution from the sign-reversed terms is suppressed in the semiclassical regime and the results match those of conventional Regge calculus.

Original languageEnglish (US)
Pages (from-to)546-568
Number of pages23
JournalNuclear Physics B
Volume808
Issue number3
DOIs
StatePublished - Feb 21 2009

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calculus
foams
triangulation
gravitons
geometry
configurations
expansion
propagation
approximation

All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics

Cite this

Bianchi, Eugenio ; Satz, Alejandro. / Semiclassical regime of Regge calculus and spin foams. In: Nuclear Physics B. 2009 ; Vol. 808, No. 3. pp. 546-568.
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Semiclassical regime of Regge calculus and spin foams. / Bianchi, Eugenio; Satz, Alejandro.

In: Nuclear Physics B, Vol. 808, No. 3, 21.02.2009, p. 546-568.

Research output: Contribution to journalArticle

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