Optimal maps in essentially non-branching spaces
Abstract
In this paper we prove that in a metric measure space (X,d,đȘ) verifying the measure contraction property with parameters Kââ and 1<N<â, any optimal transference plan between two marginal measures is induced by an optimal map, provided the first marginal is absolutely continuous with respect to đȘ and the space itself is essentially non-branching. In particular this shows that there exists a unique transport plan and it is induced by a map.