Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9860871 | Physics Letters B | 2005 | 6 Pages |
Abstract
We study the WKB approximation beyond leading order for cosmological perturbations during inflation. To first order in the slow-roll parameters, we show that an improved WKB approximation leads to analytical results agreeing to within 0.1% with the standard slow-roll results. Moreover, the leading WKB approximation to second order in the slow-roll parameters leads to analytical predictions in qualitative agreement with those obtained by the Green's function method.
Related Topics
Physical Sciences and Engineering
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Authors
Roberto Casadio, Fabio Finelli, Mattia Luzzi, Giovanni Venturi,