The dearth of halo dwarf galaxies: Is there power on short scales?

N-body simulations of structure formation with scale-invariant primordial p erturbations show significantly more virialized objects of dwarf-galaxy mas s in a typical galactic halo than are observed around the Milky Way. We sho w that the dearth of observed dwarf galaxies could be explained by a dramat ic downturn in the power spectrum at small distance scales. This suppressio n of small-scale power might also help mitigate the disagreement between cu spy simulated halos and smooth observed halos, while remaining consistent w ith Lyman-alpha-forest constraints on small-scale power. Such a spectrum co uld arise in inflationary models with broken-scale invariance.