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

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 ∼ 0.20 allows coupling levels β ≃ 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.