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Analytic solutions of scalar perturbations induced by scalar perturbations

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 نشر من قبل Keisuke Inomata
 تاريخ النشر 2020
  مجال البحث فيزياء
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 تأليف Keisuke Inomata




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We study scalar perturbations induced by scalar perturbations through the non-linear interaction appearing at second order in perturbations. We derive analytic solutions of the induced scalar perturbations in a perfect fluid. In particular, we consider the perturbations in a radiation-dominated era and a matter-dominated era. With the analytic solutions, we also discuss the power spectra of the induced perturbations.



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