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General Relativity and Gravitation

, Volume 43, Issue 9, pp 2421–2436 | Cite as

Asymptotics of 4d spin foam models

  • John W. Barrett
  • Richard J. Dowdall
  • Winston J. FairbairnEmail author
  • Henrique Gomes
  • Frank Hellmann
  • Roberto Pereira
Research Article

Abstract

We study the asymptotic properties of four-simplex amplitudes for various four-dimensional spin foam models. We investigate the semi-classical limit of the Ooguri, Euclidean and Lorentzian EPRL models using coherent states for the boundary data. For some classes of geometrical boundary data, the asymptotic formulae are given, in all three cases, by simple functions of the Regge action for the four-simplex geometry.

Keywords

Quantum gravity Spin foam models 

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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • John W. Barrett
    • 1
  • Richard J. Dowdall
    • 1
  • Winston J. Fairbairn
    • 1
    • 2
    Email author
  • Henrique Gomes
    • 1
  • Frank Hellmann
    • 1
  • Roberto Pereira
    • 3
    • 4
  1. 1.School of Mathematical Sciences, University of NottinghamNottinghamUK
  2. 2.Department MathematikUniversität HamburgHamburgGermany
  3. 3.Centre de Physique ThéoriqueMarseille Cedex 9France
  4. 4.MPI für Gravitationsphysik, Albert Einstein InstitutePotsdamGermany

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