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Title: Generalized group field theories and quantum gravity transition amplitudes

Abstract

We construct a generalized formalism for group field theories, in which the domain of the field is extended to include additional proper time variables, as well as their conjugate mass variables. This formalism allows for different types of quantum gravity transition amplitudes in perturbative expansion, and we show how both causal spin foam models and the usual a-causal ones can be derived from it, within a sum over triangulations of all topologies. We also highlight the relation of the so-derived causal transition amplitudes with simplicial gravity actions.

Authors:
 [1]
  1. D.A.M.T.P.-University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom)
Publication Date:
OSTI Identifier:
20782589
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevD.73.061502; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; COSMOLOGY; GRAVITATION; MASS; QUANTUM GRAVITY; SPIN; TOPOLOGY; TRANSITION AMPLITUDES

Citation Formats

Oriti, Daniele. Generalized group field theories and quantum gravity transition amplitudes. United States: N. p., 2006. Web. doi:10.1103/PHYSREVD.73.061502.
Oriti, Daniele. Generalized group field theories and quantum gravity transition amplitudes. United States. doi:10.1103/PHYSREVD.73.061502.
Oriti, Daniele. Wed . "Generalized group field theories and quantum gravity transition amplitudes". United States. doi:10.1103/PHYSREVD.73.061502.
@article{osti_20782589,
title = {Generalized group field theories and quantum gravity transition amplitudes},
author = {Oriti, Daniele},
abstractNote = {We construct a generalized formalism for group field theories, in which the domain of the field is extended to include additional proper time variables, as well as their conjugate mass variables. This formalism allows for different types of quantum gravity transition amplitudes in perturbative expansion, and we show how both causal spin foam models and the usual a-causal ones can be derived from it, within a sum over triangulations of all topologies. We also highlight the relation of the so-derived causal transition amplitudes with simplicial gravity actions.},
doi = {10.1103/PHYSREVD.73.061502},
journal = {Physical Review. D, Particles Fields},
number = 6,
volume = 73,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}
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