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Is Supernovae Data in Favour of Isotropic Cosmologies?

Mariusz P. Dabrowski
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Abstract

Most of the observational claims in cosmology are based on the assumption that the universe is isotropic and homogeneous so they essentially test different types of Friedmann models. This also refers to recent observations of supernovae Ia, which, within the framework of Friedmann cosmologies give strong support to negative pressure matter and also weaken the age conflict. In this essay we drop the assumption of homogeneity, though temporarily leaving the assumption of isotropy with respect to one point, and show that supernovae data can be consistent with a model of the universe with inhomogeneous pressure known as the Stephani model. Being consistent with supernovae data we are able to get the age of the universe in this model to be about 3.8 Gyr more than in its Friedmann counterpart.

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Mariusz P. Dabrowski. 1999-05-21. Is Supernovae Data in Favour of Isotropic Cosmologies?. https://arxiv.org/abs/gr-qc/9905083

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