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wolram
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I admit i know little about this subject, but am interested in any thing that solves the singularity problem.
May be some one will look at this paper to see if it makes sense
arXiv:1709.09794 (cross-list from gr-qc) [pdf, other]
Falsifying cosmological models based on a non-linear electrodynamics
Ali Övgün, Genly Leon (Catolica del Norte U.), Juan Magaña, Kimet Jusufi
Comments: 36 pages, 14 figures
Subjects: General Relativity and Quantum Cosmology (gr-qc); Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Theory (hep-th)
Recently, the nonlinear electrodynamics (NED) has been gaining attention to generate primordial magnetic fields in the Universe and also to resolve singularity problems. Moreover, recent works have shown the crucial role of the NED on the inflation. This paper provides a new approach based on a new model of NED as a source of gravitation to remove the cosmic singularity at the big bang and explain the cosmic acceleration during the inflation era without initial singularity on the background of stochastic magnetic field. We explore whether a NED field can be the origin of the cosmic acceleration. Also, we found a realization of a cyclic Universe, free of initial singularity, due the model for the NED energy density we propose. We find explicit relations for H(z) by direct integration of the equations of motion of the proposed model. We perform MCMC likelihood exploration of these relations using Observational Hubble data to find the mean values for the NED parameters. We compute the deceleration parameter q(z) in the range 0<z<2 from the best fit values of the parameters and find q(z)→1/2 at z→∞. Moreover, the Universe passes of a decelerated phase to an accelerated stage at redshift ∼0.5. The result is that the are not statistical differences with the usual model during the radiation epoch which holds for α=0. However, taking α slightly different from zero, we find that the NED with dust matter (wm=0) is able to drive the late-time cosmic acceleration of the standard cosmological model.
.
May be some one will look at this paper to see if it makes sense
arXiv:1709.09794 (cross-list from gr-qc) [pdf, other]
Falsifying cosmological models based on a non-linear electrodynamics
Ali Övgün, Genly Leon (Catolica del Norte U.), Juan Magaña, Kimet Jusufi
Comments: 36 pages, 14 figures
Subjects: General Relativity and Quantum Cosmology (gr-qc); Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Theory (hep-th)
Recently, the nonlinear electrodynamics (NED) has been gaining attention to generate primordial magnetic fields in the Universe and also to resolve singularity problems. Moreover, recent works have shown the crucial role of the NED on the inflation. This paper provides a new approach based on a new model of NED as a source of gravitation to remove the cosmic singularity at the big bang and explain the cosmic acceleration during the inflation era without initial singularity on the background of stochastic magnetic field. We explore whether a NED field can be the origin of the cosmic acceleration. Also, we found a realization of a cyclic Universe, free of initial singularity, due the model for the NED energy density we propose. We find explicit relations for H(z) by direct integration of the equations of motion of the proposed model. We perform MCMC likelihood exploration of these relations using Observational Hubble data to find the mean values for the NED parameters. We compute the deceleration parameter q(z) in the range 0<z<2 from the best fit values of the parameters and find q(z)→1/2 at z→∞. Moreover, the Universe passes of a decelerated phase to an accelerated stage at redshift ∼0.5. The result is that the are not statistical differences with the usual model during the radiation epoch which holds for α=0. However, taking α slightly different from zero, we find that the NED with dust matter (wm=0) is able to drive the late-time cosmic acceleration of the standard cosmological model.
.