Higher neutrino mass allowed if Cold Dark Matter and Dark Energy are coupled

G. La Vacca; S. A. Bonometto; L. P. L. Colombo

doi:10.1016/j.newast.2008.12.004

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arXiv · 0810.0127

Higher neutrino mass allowed if Cold Dark Matter and Dark Energy are coupled

G. La Vacca·S. A. Bonometto·L. P. L. Colombo

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Abstract

Cosmological limits on neutrino masses are softened, by more than a factor 2, if Cold Dark Matter (CDM) and Dark Energy (DE) are coupled. In turn, a neutrino mass yielding $Ω_ν$ up to $\sim0.20$ allows coupling levels $β\simeq 0.15, $ or more, already easing the coincidence problem. The coupling, in fact, displaces both $P(k)$ and $C_l$ spectra in a fashion opposite to neutrino mass. Estimates are obtained through a Fisher--matrix technique.

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G. La Vacca, S. A. Bonometto, L. P. L. Colombo. 2008-12-12. Higher neutrino mass allowed if Cold Dark Matter and Dark Energy are coupled. https://doi.org/10.1016/j.newast.2008.12.004

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