{ "id": "1001.2301", "version": "v4", "published": "2010-01-14T20:09:12.000Z", "updated": "2010-10-11T20:41:34.000Z", "title": "Primordial Power Spectra from Anisotropic Inflation", "authors": [ "Timothy R. Dulaney", "Moira I. Gresham" ], "comment": "25 pages, 2 figures; References added, typos corrected and some discussion expanded; version submitted for publication in PRD", "journal": "Phys.Rev.D81:103532,2010", "doi": "10.1103/PhysRevD.81.103532", "categories": [ "astro-ph.CO" ], "abstract": "We examine cosmological perturbations in a dynamical theory of inflation in which an Abelian gauge field couples directly to the inflaton, breaking conformal invariance. When the coupling between the gauge field and the inflaton takes a specific form, inflation becomes anisotropic and anisotropy can persist throughout inflation, avoiding Wald's no-hair theorem. After discussing scenarios in which anisotropy can persist during inflation, we calculate the dominant effects of a small persistent anisotropy on the primordial gravitational wave and curvature perturbation power spectra using the \"in-in\" formalism of perturbation theory. We find that the primordial power spectra of cosmological perturbations gain significant direction dependence and that the fractional direction dependence of the tensor power spectrum is suppressed in comparison to that of the scalar power spectrum.", "revisions": [ { "version": "v4", "updated": "2010-10-11T20:41:34.000Z" } ], "analyses": { "subjects": [ "04.40.Nr", "98.80.Cq" ], "keywords": [ "power spectrum", "primordial power spectra", "anisotropic inflation", "gauge field couples", "perturbations gain significant direction dependence" ], "tags": [ "journal article" ], "publication": { "publisher": "APS", "journal": "Physical Review D", "year": 2010, "month": "May", "volume": 81, "number": 10, "pages": 103532 }, "note": { "typesetting": "TeX", "pages": 25, "language": "en", "license": "arXiv", "status": "editable", "inspire": 842775, "adsabs": "2010PhRvD..81j3532D" } } }