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Open and closed CDM isocurvature models contrasted with the CMB data

Kari Enqvist·Hannu Kurki-Suonio·Jussi Valiviita
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Abstract

We consider pure isocurvature cold dark matter models in the case of open and closed universe. We allow for a large spectral tilt and scan the 6-dimensional parameter space for the best fit to the COBE, Boomerang, and Maxima-1 data. Taking into account constraints from large-scale structure and big bang nucleosynthesis, we find a best fit with $χ^2 = 121$, which is to be compared to $χ^2 = 44$ of a flat adiabatic reference model. Hence the current data strongly disfavour pure isocurvature perturbations.

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Kari Enqvist, Hannu Kurki-Suonio, Jussi Valiviita. 2001-12-07. Open and closed CDM isocurvature models contrasted with the CMB data. https://doi.org/10.1103/physrevd.65.043002

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