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

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 نشر من قبل Giuseppe La Vacca
 تاريخ النشر 2008
  مجال البحث فيزياء
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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 $Omega_ u$ up to $sim0.20$ allows coupling levels $beta 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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