Double power series method for approximating cosmological perturbations
نویسندگان
چکیده
منابع مشابه
Method of comparison equations for cosmological perturbations
We apply the method of comparison equations to study cosmological perturbations during inflation, obtaining the full power spectra of scalar and tensor perturbations to first and to second order in the slow-roll parameters. We compare our results with those derived by means of other methods, in particular the Green’s function method and the improved WKB approximation, and find agreement for the...
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ژورنال
عنوان ژورنال: Physical Review D
سال: 2017
ISSN: 2470-0010,2470-0029
DOI: 10.1103/physrevd.95.083526