Effective dynamics of scalar perturbations in a flat Friedmann-Robertson-Walker spacetime in Loop Quantum Cosmology

Autor: Javier Olmedo, Mikel Fernández-Méndez, Guillermo A. Mena Marugán
Rok vydání: 2014
Předmět:
Zdroj: Digital.CSIC. Repositorio Institucional del CSIC
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DOI: 10.48550/arxiv.1401.5256
Popis: 16 pags. ; 9 figs. ; A-C Apps. ; PACS numbers: 04.60.Pp, 04.60.Kz, 98.80.Qc
We study the evolution of a homogeneous and isotropic spacetime for which the spatial sections have three-torus topology, coupled to a massless scalar field with small scalar perturbations within loop quantum cosmology. We consider a proposal for the effective dynamics based on a previous hybrid quantization completed by us. Consequently, we introduce a convenient gauge fixing and adopt reduced canonical variables adapted to that hybrid quantum description. Besides, we keep backreaction contributions on the background coming from terms quadratic in the perturbations in the action of the system. We carry out a numerical analysis assuming that the inhomogeneities were in a massless vacuum state at distant past (where the initial data are set). At distant future, we observe a statistical amplification of the modes amplitude in the infrared region, as well as a phase synchronization arising from quantum gravity phenomena. A description of the perturbations in terms of the Mukhanov-Sasaki gauge invariants provides the same qualitative results. Finally, we analyze some consequences of the backreaction in our effective description. © 2014 American Physical Society.
This work was supported by PEDECIBA (Uruguay) and the Projects No. MICINN/ MINECO FIS2011-30145-C03-02 and No. CPAN CSD2007-00042 from Spain. M. F.-M. acknowledges CSIC and the European Social Fund for support under the Grant No. JAEPre_2010_01544.
Databáze: OpenAIRE
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