2017/03/31 by Jaume de Haro, Jaume Haro, Jaume Amorós +1 · 1 citation
Physics and Astronomy · #Astrophysics #Black Holes and Theoretical Physics #Classical mechanics #Cosmology #Cosmology and Gravitation Theories #Dark energy #Ekpyrotic universe #Galaxies: Formation, Evolution, Phenomena #Hubble volume #Hubble's law #Loop quantum cosmology #Metric expansion of space #Nuclear reaction #Nucleosynthesis #Physics #Quantum #Quantum cosmology #Quantum gravity #Quantum mechanics #Scalar field #Theoretical physics #Universe #gr-qc
paper · pdf · doi:10.1088/1475-7516/2017/09/002
published as JCAP 09 (2017) 002 · 39 pages, 19 figures. Version accepted for publication in JCAP
arxiv created 2017/08/13 · openalex publication_date 2017/09/01 · arxiv updated 2017/09/04 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We will perform a detailed study of the matter-ekpyrotic bouncing scenario in Loop Quantum Cosmology using the methods of the dynamical systems theory. We will show that when the background is driven by a single scalar field, at very late times, in the contracting phase, all orbits depict a matter dominated Universe, which evolves to an ekpyrotic phase. After the bounce the Universe enters in the expanding phase, where the orbits leave the ekpyrotic regime going to a kination (also named deflationary) regime. Moreover, this scenario supports the production of heavy massive particles conformally coupled with gravity, which reheats the universe at temperatures compatible with the nucleosynthesis bounds and also the production of massless particles non-conformally coupled with gravity leading to very high reheating temperatures but ensuring the nucleosynthesis success. Dealing with cosmological perturbations, these background dynamics produce a nearly scale invariant power spectrum for the modes that leave the Hubble radius, in the contracting phase, when the Universe is quasi-matter dominated, whose spectral index and corresponding running is compatible with the recent experimental data obtained by PLANCK's team.