Cosmological Perturbations in Einstein-Aether Theories

In this thesis we study the Einstein-Aether (E-A) theory from the point of view of its cosmological perturbations. We are interested in the constraints that may be obtained from this analysis and the special features that can arise from the vector mode, absent in General Relativity. We apply the the...

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Detalhes bibliográficos
Autor: Fariña Sierra, Noela
Formato: tesis doctoral
Estado:Versión publicada
Fecha de publicación:2011
País:España
Recursos:CBUC, CESCA
Repositorio:TDR. Tesis Doctorales en Red
OAI Identifier:oai:www.tdx.cat:10803/111045
Acesso em linha:http://hdl.handle.net/10803/111045
Access Level:acceso abierto
Palavra-chave:Cosmologia
Cosmología
Cosmology
Relativitat (Física)
Relatividad (Física)
Relativity (Physics)
Gravitació
Gravitación
Gravitation
Ciències Experimentals i Matemàtiques
53
Descrição
Resumo:In this thesis we study the Einstein-Aether (E-A) theory from the point of view of its cosmological perturbations. We are interested in the constraints that may be obtained from this analysis and the special features that can arise from the vector mode, absent in General Relativity. We apply the theory of linear perturbations in an expanding universe to describe the growth of inhomogeneities on subhorizon scales after recombination. We can split the perturbations in the different modes (scalar, vector and tensor) and we can study each of them separately. This allow us to obtain the stability conditions for this kind of theories and we can also obtain the power spectrum for each mode. For the scalar modes, we calculate the subhorizon solutions during the radiation and matter domination epochs. We are also interested in the effect of the theory in the Cosmic Microwave Background anisotropies, in particular in the contribution of the vector modes, as these modes are absent in General Relativity. We analyze the solutions for radiation and matter and calculate the angular power spectrum at large and small angular scales. This allows us to compare the contribution of the vector modes with the one coming from the tensor ones and with observations. The last issue we address is the effects of the vector modes in the polarization of the Cosmic Microwave Background.