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Another model for the regularized big bang

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 نشر من قبل Frans Klinkhamer
 تاريخ النشر 2020
  مجال البحث فيزياء
والبحث باللغة English
 تأليف F.R. Klinkhamer




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We propose a gravitational model with a Brans-Dicke-type scalar field having, in the would-be action, a wrong-sign kinetic term and a quartic interaction term. In a cosmological context, we obtain, depending on the boundary conditions, either the Friedmann solution or a kink-bounce solution. The expanding-universe Friedmann solution has a big bang curvature singularity, whereas the kink-bounce solution has a nonsingular bouncing behavior of the cosmic scale factor. The bounce occurs precisely at the moment when the scalar field of the kink-type configuration goes through zero, making for a vanishing effective gravitational coupling.



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