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arXiv · 0712.3602

Testing power-law cosmology with galaxy clusters

Zong-Hong Zhu·Ming Hu·J. S. Alcaniz·Yu-Xing Liu
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Abstract

Power-law cosmologies, in which the cosmological scale factor evolves as a power law in the age, $a \propto t^α$ with $α\ga 1$, regardless of the matter content or cosmological epoch, is comfortably concordant with a host of cosmological observations.} {In this article, we use recent measurements of the X-ray gas mass fractions in clusters of galaxies to constrain the $α$ parameter with curvature $k = \pm1, 0$. We find that the best fit happens for an open scenario with the power index $α= 1.14 \pm 0.05$, though the flat and closed model can not be rule out at very high confidence level.} {Our results are in agreement with other recent analyses and show that the X-ray gas mass fraction measurements in clusters of galaxies provide a complementary test to the power law cosmology.

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Zong-Hong Zhu, Ming Hu, J. S. Alcaniz, Yu-Xing Liu. 2007-12-21. Testing power-law cosmology with galaxy clusters. https://doi.org/10.1051/0004-6361:20077797

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