Florian Fuehrer (Institut fuer Theoretische Physik, Germany)
In Growing Neutrino Quintessence strong backreaction effects, induced from large neutrino non-linearities, alter the cosmic history. I will present results obtained from N-body simulations which includes relativistic particles, non-linear scalar field equations and backreaction effects. Including the backreaction effects a realistic cosmology is hard to realize. This points to the need of models with field dependent couplings. In those models the neutrino perturbations are still large, but the backreaction effects are much smaller, a realistic cosmology is possible.