Towards spinfoam cosmology

Journal Article · Fri Oct 15 04:00:00 EDT 2010 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.82.084035· OSTI ID:21433015

Bianchi, Eugenio; Rovelli, Carlo ^[1]; Vidotto, Francesca ^[1]

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1. Centre de Physique Theorique de Luminy, Case 907, F-13288 Marseille (France)

We compute the transition amplitude between coherent quantum states of geometry peaked on homogeneous-isotropic metrics. We work in the context of pure gravity without matter, we use the holomorphic representations of loop quantum gravity and the Kaminski-Kisielowski-Lewandowski generalization of the new vertex, and work at first order in the vertex expansion, second order in the graph (multipole) expansion, and first order in volume{sup -1}. We show that the resulting amplitude is in the kernel of a differential operator whose classical limit is the canonical Hamiltonian of a Friedmann-Robertson-Walker cosmology. This result is an indication that the dynamics of loop quantum gravity defined by the new vertex reproduces the gravity part of the Friedmann equation in the appropriate limit.

• OSTI ID: 21433015
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 8 Vol. 82; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
79 ASTRONOMY AND ASTROPHYSICS
AMPLITUDES
COSMOLOGY
EQUATIONS
EXPANSION
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GRAVITATION
HAMILTONIANS
MATHEMATICAL OPERATORS
METRICS
QUANTUM FIELD THEORY
QUANTUM GRAVITY
QUANTUM OPERATORS
TRANSITION AMPLITUDES