Author:
Jercher Alexander F.,Oriti Daniele,Pithis Andreas G. A.
Abstract
Abstract
We study the cosmological sector of the Lorentzian Barrett-Crane (BC) model coupled to a free massless scalar field in its Group Field Theory (GFT) formulation, corresponding to the mean-field hydrodynamics obtained from coherent condensate states. The relational evolution of the condensate with respect to the scalar field yields effective dynamics of homogeneous and isotropic cosmologies, similar to those previously obtained in SU(2)-based EPRL-like models. Also in this manifestly Lorentzian setting, in which only continuous SL(2,ℂ)-representations are used, we obtain generalized Friedmann equations that generically exhibit a quantum bounce, and can reproduce all of the features of the cosmological dynamics of EPRL-like models. This lends support to the expectation that the EPRL-like and BC models may lie in the same continuum universality class, and that the quantum gravity mechanism producing effective bouncing scenarios may not depend directly on the discretization of geometric observables.
Subject
Astronomy and Astrophysics
Reference141 articles.
1. A short review of loop quantum gravity;Ashtekar;Rept. Prog. Phys.,2021
2. Gravitational-wave luminosity distance in quantum gravity;Calcagni;Phys. Lett. B,2019
3. Quantum gravity phenomenology at the dawn of the multi-messenger era – A review;Addazi,2021
4. Dark Energy from Structure: a Status Report;Buchert;Gen. Rel. Grav.,2008
5. Is there proof that backreaction of inhomogeneities is irrelevant in cosmology?;Buchert;Class. Quant. Grav.,2015
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