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Non-perturbative gauge invariant scalar fluctuations of the metric in Higgs inflation from complex geometrical scalar-tensor theory of gravity

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 نشر من قبل Jose Edgar Madriz Aguilar Dr.
 تاريخ النشر 2020
  مجال البحث فيزياء
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In this letter we investigate gauge invariant scalar fluctuations of the metric in a non-perturbative formalism for a Higgs inflationary model recently introduced in the framework of a geometrical scalar-tensor theory of gravity. In this scenario the Higgs inflaton field has its origin in the Weyl scalar field of the background geometry. We found a nearly scale invariance of the power spectrum for linear scalar fluctuations of the metric. For certain parameters of the model we obtain values for the scalar spectral index $n_s$ and the scalar to tensor ratio $r$ that fit well with the Planck 2018 results. Besides we show that in this model the trans-planckian problem can be avoided.



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