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The Evolution of Non-adiabatic Pressure Perturbations during Multi-field Inflation

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 نشر من قبل Ian Huston
 تاريخ النشر 2012
  مجال البحث فيزياء
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Non-adiabatic pressure perturbations naturally occur in models of inflation consisting of more than one scalar field. The amount of non-adiabatic pressure present at the end of inflation can have observational consequences through changes in the curvature perturbation, the generation of vorticity and subsequently the sourcing of B-mode polarisation. In this work, based on a presentation at the 13th Marcel Grossmann Meeting, we give a very brief overview of non-adiabatic pressure perturbations in multi-field inflationary models and describe our recent calculation of the spectrum of isocurvature perturbations generated at the end of inflation for different models which have two scalar fields.


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