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Age of the Universe in the Cardassian Model

Christopher Savage·Noriyuki Sugiyama·Katherine Freese
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Abstract

The age of the universe is obtained in a subset of Cardassian models by using WMAP data. Cardassian expansion is a modification to the Friedmann equation that allows the universe to be flat, matter dominated, and accelerating, without a vacuum component. Since this model changes the evolution of the universe, we should not a priori expect the Cardassian age to be the same as the WMAP Friedmann derived result of 13.7 +/- 0.2 Gyrs. However, in the subset of Cardassian models we consider, we discover that the age of the universe varies from 13.4 - 13.8 Gyr over the range of parameter space we explore, a result close to that of the standard Lambda Cold Dark Matter model. The Hubble constant h, which may also vary in these models, likewise varies little from the Friedmann result.

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Christopher Savage, Noriyuki Sugiyama, Katherine Freese. 2005-09-30. Age of the Universe in the Cardassian Model. https://doi.org/10.1088/1475-7516%2F2005%2F10%2F007

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