%0 Journal Article %T Polytopal Estimate of Mirkovic-Vilonen polytopes lying in a Demazure crystal %A Syu Kato %A Satoshi Naito %A Daisuke Sagaki %J Mathematics %D 2009 %I arXiv %X In this paper, we give a polytopal estimate of Mirkovi\'c-Vilonen polytopes lying in a Demazure crystal in terms of Minkowski sums of extremal Mirkovi\'c-Vilonen polytopes. As an immediate consequence of this result, we provide a necessary (but not sufficient) polytopal condition for a Mirkovi\'c-Vilonen polytope to lie in a Demazure crystal. %U http://arxiv.org/abs/0912.0586v2