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Cosmological Perturbations in the Healthy Extension of Horava-Lifshitz gravity

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 نشر من قبل Robert Brandenberger
 تاريخ النشر 2010
  مجال البحث فيزياء
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We study linear cosmological perturbations in the ``healthy extension of Horava-Lifshitz gravity which has recently been analyzed cite{BPS2}. We find that there are two degrees of freedom for scalar metric fluctuations, but that one of them decouples in the infrared limit. Also, for appropriate choices of the parameters defining the Lagrangian, the extra mode can be made well-behaved even in the ultraviolet.



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