Primordial Magnetic Field from Gravitationally Coupled Electrodynamics in Bouncing Scenario

Autor: Chen, Jie-Wen, Li, Chong-Huan, Li, Yu-Bin, Zhu, Mian
Rok vydání: 2017
Předmět:
Druh dokumentu: Working Paper
Popis: We in this paper study the generation of primordial magnetic field (PMF) in the non-singular bouncing scenario, through the coupling of the electromagnetic field to gravity. We adopt an electrodynamic model with a coupling coefficient as a function of the scale factor $a$, i.e. $f=1+(a/a_\star)^{-n}$, with $a_\star$ and $n>0$ being constants. The result implies that in this mechanism, the power spectrum of PMF today is always blue tilted on large scales from $1$ Mpc to the Hubble length, and the observational constraints favor the ekpyrotic-bounce scenario. Furthermore, the back reaction of the energy density of PMF at the bouncing point yields theoretical constraints on the bouncing model.
Databáze: arXiv
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