The structure of Doppler peaks induced by active perturbations
We investigate how the qualitative structure of Doppler peaks in the angular power spectrum of the cosmic microwave anisotropy is affected by basic assumptions going into theories of structure formation. We define the concepts of ``coherent'' and ``incoherent'' fluctuations, and...
| Main Authors: | , , , |
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| Format: | Journal article |
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1996
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| _version_ | 1797058226911444992 |
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| author | Magueijo, J Albrecht, A Ferreira, P Coulson, D |
| author_facet | Magueijo, J Albrecht, A Ferreira, P Coulson, D |
| author_sort | Magueijo, J |
| collection | OXFORD |
| description | We investigate how the qualitative structure of Doppler peaks in the angular power spectrum of the cosmic microwave anisotropy is affected by basic assumptions going into theories of structure formation. We define the concepts of ``coherent'' and ``incoherent'' fluctuations, and also of ``active'' and ``passive'' fluctuations. In these terms inflationary fluctuations are passive and coherent while topological defects are active incoherent fluctuations. Causality and scale invariance are shown to have different implementations in theories differing in the above senses. We then extend the formalism of Hu and Sugiyama to treat models with cosmic defects. Using this formalism we show that the existence or absence of secondary Doppler peaks and the rough placing of the primary peak are very sensitive to the fundamental properties defined. We claim therefore that even a rough measurement of the angular power spectrum $C_l$ shape at $100 |
| first_indexed | 2024-03-06T19:47:32Z |
| format | Journal article |
| id | oxford-uuid:22d701f1-f8d7-4358-8dc4-5f4f8f11ba85 |
| institution | University of Oxford |
| last_indexed | 2024-03-06T19:47:32Z |
| publishDate | 1996 |
| record_format | dspace |
| spelling | oxford-uuid:22d701f1-f8d7-4358-8dc4-5f4f8f11ba852022-03-26T11:40:48ZThe structure of Doppler peaks induced by active perturbationsJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:22d701f1-f8d7-4358-8dc4-5f4f8f11ba85Symplectic Elements at Oxford1996Magueijo, JAlbrecht, AFerreira, PCoulson, DWe investigate how the qualitative structure of Doppler peaks in the angular power spectrum of the cosmic microwave anisotropy is affected by basic assumptions going into theories of structure formation. We define the concepts of ``coherent'' and ``incoherent'' fluctuations, and also of ``active'' and ``passive'' fluctuations. In these terms inflationary fluctuations are passive and coherent while topological defects are active incoherent fluctuations. Causality and scale invariance are shown to have different implementations in theories differing in the above senses. We then extend the formalism of Hu and Sugiyama to treat models with cosmic defects. Using this formalism we show that the existence or absence of secondary Doppler peaks and the rough placing of the primary peak are very sensitive to the fundamental properties defined. We claim therefore that even a rough measurement of the angular power spectrum $C_l$ shape at $100 |
| spellingShingle | Magueijo, J Albrecht, A Ferreira, P Coulson, D The structure of Doppler peaks induced by active perturbations |
| title | The structure of Doppler peaks induced by active perturbations |
| title_full | The structure of Doppler peaks induced by active perturbations |
| title_fullStr | The structure of Doppler peaks induced by active perturbations |
| title_full_unstemmed | The structure of Doppler peaks induced by active perturbations |
| title_short | The structure of Doppler peaks induced by active perturbations |
| title_sort | structure of doppler peaks induced by active perturbations |
| work_keys_str_mv | AT magueijoj thestructureofdopplerpeaksinducedbyactiveperturbations AT albrechta thestructureofdopplerpeaksinducedbyactiveperturbations AT ferreirap thestructureofdopplerpeaksinducedbyactiveperturbations AT coulsond thestructureofdopplerpeaksinducedbyactiveperturbations AT magueijoj structureofdopplerpeaksinducedbyactiveperturbations AT albrechta structureofdopplerpeaksinducedbyactiveperturbations AT ferreirap structureofdopplerpeaksinducedbyactiveperturbations AT coulsond structureofdopplerpeaksinducedbyactiveperturbations |