Influence of superhorizon scales on cosmological observables generated during inflation

[EN]In the framework known as stochastic inflation, the evolution of cosmological perturbations picks up a noise term. In this article we focus on the fact that in realistic applications of the model, the noise is actually coloured, which leads to memory effects of modes of different scales. We eval...

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Detalles Bibliográficos
Autores: Matarrese, Sabino, Musso, Marcello, Riotto, Antonio
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2004
País:España
Institución:Universidad de Salamanca (USAL)
Repositorio:GREDOS. Repositorio Institucional de la Universidad de Salamanca
OAI Identifier:oai:gredos.usal.es:10366/169089
Acceso en línea:http://hdl.handle.net/10366/169089
Access Level:acceso abierto
Palabra clave:Fondo Cósmico de Microondas (teoría)
Perturbaciones cosmológicas
Inflación
Descripción
Sumario:[EN]In the framework known as stochastic inflation, the evolution of cosmological perturbations picks up a noise term. In this article we focus on the fact that in realistic applications of the model, the noise is actually coloured, which leads to memory effects of modes of different scales. We evaluate the two- and three-point correlation function for the simple toy model of a scalar field with cubic self-interactions in a fixed de Sitter background. We show that in the presence of coloured noise perturbations of observable scale preserve some memory of the super-horizon modes, as scale-dependent imprints in their statistical moments. In particular, we find a blue tilt of the power-spectrum on large scales, and an enhancement of intrinsic non-Gaussianity.