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arXiv · 1403.6396

Viability of the matter bounce scenario in Loop Quantum Cosmology from BICEP2 last data

Jaume de Haro·Jaume Amorós
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Abstract

The CMB map provided by the Planck project constrains the value of the ratio of tensor-to-scalar perturbations, namely $r$, to be smaller than $0.11$ (95% CL). This bound rules out the simplest models of inflation. However, recent data from BICEP2 is in strong tension with this constrain, as it finds a value $r=0.20^{+0.07}_{-0.05}$ with $r=0$ disfavored at $7.0 σ$, which allows these simplest inflationary models to survive. The remarkable fact is that, even though the BICEP2 experiment was conceived to search for evidence of inflation, its experimental data matches correctly theoretical results coming from the matter bounce scenario (the alternative model to the inflationary paradigm). More precisely, most bouncing cosmologies do not pass Planck's constrains due to the smallness of the value of the tensor/scalar ratio $r\leq 0.11$, but with new BICEP2 data some of them fit well with experimental data. This is the case with the matter bounce scenario in the teleparallel version of Loop Quantum Cosmology.

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Jaume de Haro, Jaume Amorós. 2014-07-02. Viability of the matter bounce scenario in Loop Quantum Cosmology from BICEP2 last data. https://doi.org/10.1088/1475-7516%2F2014%2F08%2F025

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