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Global cosmological dynamics for the scalar field representation of the modified Chaplygin gas

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 نشر من قبل Claes Uggla
 تاريخ النشر 2013
  مجال البحث فيزياء
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 تأليف Claes Uggla




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In this paper we investigate the global dynamics for the minimally coupled scalar field representation of the modified Chaplygin gas in the context of flat FLRW cosmology. The tool for doing this is a new set of bounded variables that lead to a regular dynamical system. It is shown that the exact modified Chaplygin gas perfect fluid solution appears as a straight line in the associated phase plane. It is also shown that no other solutions stay close to this solution during their entire temporal evolution, but that there exists an open subset of solutions that stay arbitrarily close during an intermediate time interval, and into the future in the case the scalar field potential exhibits a global minimum.



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