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Big-bounce cosmology in the presence of Immirzi field

Flavio Bombacigno1,*, Francesco Cianfrani2,†, and Giovanni Montani3,‡

  • 1Physics Department, “Sapienza” University of Rome, Piazzale Aldo Moro 5, 00185 (Roma), Italy
  • 2Institute for Theoretical Physics, University of Wrocław, Plac Maksa Borna 9, Pl–50-204 Wrocław, Poland
  • 3ENEA, FSN-FUSPHY-TSM, R.C. Frascati, Via E. Fermi 45, 00044 Frascati, Italy and Physics Department, “Sapienza” University of Rome, Piazzale Aldo Moro 5, 00185 (Roma), Italy

  • *f.bombacigno.pli@gmail.com
  • †francesco.cianfrani@ift.uni.wroc.pl
  • ‡giovanni.montani@enea.it
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Phys. Rev. D 94, 064021 – Published 8 September, 2016

DOI: https://doi.org/10.1103/PhysRevD.94.064021

Abstract

The Immirzi parameter is promoted to be a scalar field and the Hamiltonian analysis of the corresponding dynamical system is performed in the presence of gravity. We identified some SU(2) connections, generalizing Ashtekar-Barbero variables, and we rewrite the constraints in terms of them, setting the classical formulation suitable for loop quantization. Then, we consider the reduced system obtained when restricting to a flat isotropic cosmological model. By mimicking loop quantization via an effective semiclassical treatment, we outline how quantum effects are able to tame the initial singularity both in synchronous time and when the Immirzi field is taken as a relational time.

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Outline

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Phys. Rev. D 94, 064021– Published 8 September, 2016
  • Received 4 July 2016

© 2016 American Physical Society

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