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Chaplygin gas in light of recent Integrated Sachs--Wolfe effect data

Tommaso Giannantonio·Alessandro Melchiorri
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Abstract

We investigate the possibility of constraining Chaplygin dark energy models with current Integrated Sachs Wolfe effect data. In the case of a flat universe we found that generalized Chaplygin gas models must have an energy density such that $Ω_c >0.55$ and an equation of state $w <-0.6$ at 95% c.l.. We also investigate the recently proposed Silent Chaplygin models, constraining $Ω_c >0.55$ and $w <-0.65$ at 95% c.l.. Better measurements of the CMB-LSS correlation will be possible with the next generation of deep redshift surveys. This will provide independent and complementary constraints on unified dark energy models such as the Chaplygin gas.

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Tommaso Giannantonio, Alessandro Melchiorri. 2006-06-07. Chaplygin gas in light of recent Integrated Sachs--Wolfe effect data. https://doi.org/10.1088/0264-9381%2F23%2F12%2F009

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