Inflation induced Planck-size black hole remnants as dark matter

While there exist various candidates, the identification of dark matter remains unresolved. Recently, it was argued that the generalized uncertainty principle (GUP) may prevent a black hole from evaporating completely, and as a result there should exist a Planck-sized BHR at the end of its evaporation. We speculate that the stability of BHR may be further protected by supersymmetry in the form of extremal black hole. If this is indeed the case and if a sufficient amount of small black holes can be produced in the early universe, then the resultant BHRs can be an interesting candidate for DM. We demonstrate that this is the case in the hybrid inflation model. By assuming BHR as DM, our notion imposes a constraint on the hybrid inflation potential. We show that such a constraint is not fine-tuned. Possible observational signatures are briefly discussed. (C) 2005 Published by Elsevier B.V.