A energia escura poderá forçar o universo a se desfazer gradualmente

terça-feira, novembro 15, 2016

Cosmological perturbations in an effective and genuinely phantom dark energy Universe

Source/Fonte: Thomas Gray/Millennium Images, UK
We carry out an analysis of the cosmological perturbations in general relativity for three different models which are good candidates to describe the current acceleration of the Universe. These three set-ups are described classically by perfect fluids with a phantom nature and represent deviations from the most widely accepted 
CDM model. In addition, each of the models under study induce different future singularities or abrupt events known as (i) Big Rip, (ii) Little Rip and (iii) Little Sibling of the Big Rip. Only the first one is regarded as a true singularity since it occurs at a finite cosmic time. For this reason, we refer to the others as abrupt events. With the aim to find possible footprints of this scenario in the Universe matter distribution, we not only obtain the evolution of the cosmological scalar perturbations but also calculate the matter power spectrum for each model. Finally, we constrain observationally these models using several measurements of the growth rate function, more precisely 
, and compare our results with the observational ones reaching the conclusion that even if these three models are very similar at present there are small differences that could allow us to distinguish them.
Comments:18 pages, 4 figures, 1 table. RevTeX 4.1
Subjects:Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th)
Cite as:arXiv:1611.00392 [astro-ph.CO]
 (or arXiv:1611.00392v1 [astro-ph.CO] for this version)

Submission history

From: Mariam Bouhmadi-Lopez [view email
[v1] Tue, 1 Nov 2016 21:06:33 GMT (1843kb)


NOTA DESTE BLOGGER: Calma, gente! Os cientistas pensam que isso somente ocorrerá daqui a 100 bilhões de anos!