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arXiv · astro-ph/0312534

The Integrated Sachs-Wolfe effect as a probe of non-standard cosmological evolution

T. Multamaki·O. Elgaroy
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Abstract

The Integrated Sachs-Wolfe effect is studied in non-standard cosmologies. By considering flat universes with a non-fluctuating dark energy component, it is shown how the quadrupole power can be suppressed by atypical evolution of the scale factor. For example, a brief period of non-standard evolution at a high redshift can suppress the quadrupole significantly. The effect on the overall normalization of the CMB power spectrum is also discussed. Non-standard cosmologies can affect the overall normalization significantly and enhance the primordial fluctuations. The possibility of constraining such non-standard models with CMB and independent measures of $σ_8$, is considered.

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T. Multamaki, O. Elgaroy. 2003-12-19. The Integrated Sachs-Wolfe effect as a probe of non-standard cosmological evolution. https://doi.org/10.1051/0004-6361%3A20041104

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