Analytic study of cosmological perturbations in a unified model of dark matter and dark energy with a sharp transition
Autor(a) principal: | |
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Data de Publicação: | 2018 |
Outros Autores: | , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UNESP |
Texto Completo: | http://dx.doi.org/10.1016/j.astropartphys.2018.07.005 http://hdl.handle.net/11449/184875 |
Resumo: | We study cosmological perturbations in a model of unified dark matter and dark energy with a sharp transition in the late-time universe. The dark sector is described by a dark fluid which evolves from an early stage at redshifts z>z(C) when it behaves as cold dark matter (CDM) to a late time dark energy (DE) phase (z<z(C)) when the equation of state parameter is w = -1+is an element of, with a constant is an element of which must be in the range 0 < is an element of < 2/3. We show that fluctuations in the dark energy phase suffer from an exponential instability, the mode functions growing both as a function of comoving momentum k and of conformal time eta. In order that this exponential instability does not lead to distortions of the energy density power spectrum on scales for which we have good observational results, the redshift z(C) of transition between the two phases is constrained to be so close to zero that the model is unable to explain the supernova data. (C) 2018 Elsevier B.V. All rights reserved. |
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spelling |
Analytic study of cosmological perturbations in a unified model of dark matter and dark energy with a sharp transitionWe study cosmological perturbations in a model of unified dark matter and dark energy with a sharp transition in the late-time universe. The dark sector is described by a dark fluid which evolves from an early stage at redshifts z>z(C) when it behaves as cold dark matter (CDM) to a late time dark energy (DE) phase (z<z(C)) when the equation of state parameter is w = -1+is an element of, with a constant is an element of which must be in the range 0 < is an element of < 2/3. We show that fluctuations in the dark energy phase suffer from an exponential instability, the mode functions growing both as a function of comoving momentum k and of conformal time eta. In order that this exponential instability does not lead to distortions of the energy density power spectrum on scales for which we have good observational results, the redshift z(C) of transition between the two phases is constrained to be so close to zero that the model is unable to explain the supernova data. (C) 2018 Elsevier B.V. All rights reserved.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)NSERCCanada Research Chair programMcGill Univ, Dept Phys, Montreal, PQ H3A 2T8, CanadaUniv Fed Alfenas, Inst Ciencia & Tecnol, Rodovia Jose Aurelio Vilela 11999,Cidade Univ, BR-37715400 Pocos De Caldas, MG, BrazilUniv Fed Rio Grande do Norte, Escola Ciencia & Tecnol, Campus Univ S-N, BR-59072970 Natal, RN, BrazilSao Paulo State Univ, Inst Fis Teor, POB 70532-2, BR-01156970 Sao Paulo, SP, BrazilSao Paulo State Univ, Inst Fis Teor, POB 70532-2, BR-01156970 Sao Paulo, SP, BrazilCAPES: 88881.119228/2016-01CNPq: 112861/2015-6Elsevier B.V.McGill UnivUniv Fed AlfenasUniv Fed Rio Grande do NorteUniversidade Estadual Paulista (Unesp)Cuzinatto, Rodrigo R.Medeiros, Leo G. [UNESP]Morais, Eduardo M. de [UNESP]Brandenberger, Robert H.2019-10-04T12:30:42Z2019-10-04T12:30:42Z2018-12-01info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/article98-107http://dx.doi.org/10.1016/j.astropartphys.2018.07.005Astroparticle Physics. Amsterdam: Elsevier, v. 103, p. 98-107, 2018.0927-6505http://hdl.handle.net/11449/18487510.1016/j.astropartphys.2018.07.005WOS:000445718600013Web of Sciencereponame:Repositório Institucional da UNESPinstname:Universidade Estadual Paulista (UNESP)instacron:UNESPengAstroparticle Physicsinfo:eu-repo/semantics/openAccess2021-10-23T15:54:58Zoai:repositorio.unesp.br:11449/184875Repositório InstitucionalPUBhttp://repositorio.unesp.br/oai/requestopendoar:29462024-08-05T15:27:42.230643Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)false |
dc.title.none.fl_str_mv |
Analytic study of cosmological perturbations in a unified model of dark matter and dark energy with a sharp transition |
title |
Analytic study of cosmological perturbations in a unified model of dark matter and dark energy with a sharp transition |
spellingShingle |
Analytic study of cosmological perturbations in a unified model of dark matter and dark energy with a sharp transition Cuzinatto, Rodrigo R. |
title_short |
Analytic study of cosmological perturbations in a unified model of dark matter and dark energy with a sharp transition |
title_full |
Analytic study of cosmological perturbations in a unified model of dark matter and dark energy with a sharp transition |
title_fullStr |
Analytic study of cosmological perturbations in a unified model of dark matter and dark energy with a sharp transition |
title_full_unstemmed |
Analytic study of cosmological perturbations in a unified model of dark matter and dark energy with a sharp transition |
title_sort |
Analytic study of cosmological perturbations in a unified model of dark matter and dark energy with a sharp transition |
author |
Cuzinatto, Rodrigo R. |
author_facet |
Cuzinatto, Rodrigo R. Medeiros, Leo G. [UNESP] Morais, Eduardo M. de [UNESP] Brandenberger, Robert H. |
author_role |
author |
author2 |
Medeiros, Leo G. [UNESP] Morais, Eduardo M. de [UNESP] Brandenberger, Robert H. |
author2_role |
author author author |
dc.contributor.none.fl_str_mv |
McGill Univ Univ Fed Alfenas Univ Fed Rio Grande do Norte Universidade Estadual Paulista (Unesp) |
dc.contributor.author.fl_str_mv |
Cuzinatto, Rodrigo R. Medeiros, Leo G. [UNESP] Morais, Eduardo M. de [UNESP] Brandenberger, Robert H. |
description |
We study cosmological perturbations in a model of unified dark matter and dark energy with a sharp transition in the late-time universe. The dark sector is described by a dark fluid which evolves from an early stage at redshifts z>z(C) when it behaves as cold dark matter (CDM) to a late time dark energy (DE) phase (z<z(C)) when the equation of state parameter is w = -1+is an element of, with a constant is an element of which must be in the range 0 < is an element of < 2/3. We show that fluctuations in the dark energy phase suffer from an exponential instability, the mode functions growing both as a function of comoving momentum k and of conformal time eta. In order that this exponential instability does not lead to distortions of the energy density power spectrum on scales for which we have good observational results, the redshift z(C) of transition between the two phases is constrained to be so close to zero that the model is unable to explain the supernova data. (C) 2018 Elsevier B.V. All rights reserved. |
publishDate |
2018 |
dc.date.none.fl_str_mv |
2018-12-01 2019-10-04T12:30:42Z 2019-10-04T12:30:42Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://dx.doi.org/10.1016/j.astropartphys.2018.07.005 Astroparticle Physics. Amsterdam: Elsevier, v. 103, p. 98-107, 2018. 0927-6505 http://hdl.handle.net/11449/184875 10.1016/j.astropartphys.2018.07.005 WOS:000445718600013 |
url |
http://dx.doi.org/10.1016/j.astropartphys.2018.07.005 http://hdl.handle.net/11449/184875 |
identifier_str_mv |
Astroparticle Physics. Amsterdam: Elsevier, v. 103, p. 98-107, 2018. 0927-6505 10.1016/j.astropartphys.2018.07.005 WOS:000445718600013 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
Astroparticle Physics |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
98-107 |
dc.publisher.none.fl_str_mv |
Elsevier B.V. |
publisher.none.fl_str_mv |
Elsevier B.V. |
dc.source.none.fl_str_mv |
Web of Science reponame:Repositório Institucional da UNESP instname:Universidade Estadual Paulista (UNESP) instacron:UNESP |
instname_str |
Universidade Estadual Paulista (UNESP) |
instacron_str |
UNESP |
institution |
UNESP |
reponame_str |
Repositório Institucional da UNESP |
collection |
Repositório Institucional da UNESP |
repository.name.fl_str_mv |
Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP) |
repository.mail.fl_str_mv |
|
_version_ |
1808128514730229760 |