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Turning in the landscape: a new mechanism for generating Primordial Black Holes

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 نشر من قبل Jacopo Fumagalli
 تاريخ النشر 2020
  مجال البحث فيزياء
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We propose a new model-independent mechanism for producing Primordial Black Holes from a period of multi-field inflation. The required enhancement of primordial fluctuations compared to their value at CMB scales naturally occurs when the inflationary trajectory in the landscape exhibits a limited period of strongly non-geodesic motion. Such trajectories with multiple dynamical fields are motivated by the search for ultraviolet completions of inflation. We study analytically and numerically how the parameters describing the bending impact the primordial fluctuations power spectrum and the mass function of Primordial Black Holes. Our mechanism has the potential of exhibiting unique features accessible to observation through its Primordial Black Hole spectrum and stochastic background of gravitational waves, offering a precious glimpse at the dynamics of inflation in the landscape.



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