Scalar suppression on large scales in open inflation
  We consider two toy models of open inflation and investigate their ability to give a suppression of scalar power on large scales whilst also satisfying observational constraints on the spatial curvature of the universe. Qualitatively we find that both models are indeed capable of fulfilling these two requirements, but we also see that effects of the quantum tunnelling must be carefully taken into account if we wish to make quantitative predictions. 
Jonathan White, Ying-li Zhang and Misao Sasaki
astro-ph.CO gr-qc hep-th