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$C^\infty$ perturbations of FRW models with a cosmological constant

Zoltán Perjés·Mátyás Vasúth·Viktor Czinner·Daniel Eriksson
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Abstract

Spatially homogeneous and isotropic cosmological models, with a perfect fluid matter source and non-vanishing cosmological constant, are studied. The equations governing linear perturbations of the space-time and the variation of energy density are given. The complete solution of the problem is obtained for $C^{\infty}$ perturbations, using a comoving time. The Sachs-Wolfe fluctuations of the temperature of the cosmic background radiation are obtained for the relatively growing density perturbations. It is found that the observable celestial microwave fluctuation pattern underwent a reversal approximately two billion years ago. What is observed today is a negative image of the last scattering surface with an attenuation of the fluctuations, due to the presence of the cosmological constant.

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Zoltán Perjés, Mátyás Vasúth, Viktor Czinner, Daniel Eriksson. 2004-12-20. $C^\infty$ perturbations of FRW models with a cosmological constant. https://doi.org/10.1051/0004-6361%3A20041472

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