title: Limit on nonlocality in any world in which communication complexity is not trivial.
abstract: Bell proved that quantum entanglement enables two spacelike separated parties to exhibit classically impossible correlations. Even though these correlations are stronger than anything classically achievable, they cannot be harnessed to make instantaneous (faster than light) communication possible. Yet, Popescu and Rohrlich have shown that even stronger correlations can be defined, under which instantaneous communication remains impossible. This raises the question: Why are the correlations achievable by quantum mechanics not maximal among those that preserve causality? We give a partial answer to this question by showing that slightly stronger correlations would result in a world in which communication complexity becomes trivial.
authors.affiliation: Département IRO, Université de Montréal, C.P. 6128, Succursale Centre-Ville, Montréal, Québec H3C 3J7, Canada.
authors.forename: Gilles
authors.initials: G
authors.lastname: Brassard
authors.forename: Harry
authors.initials: H
authors.lastname: Buhrman
authors.forename: Noah
authors.initials: N
authors.lastname: Linden
authors.forename: André Allan
authors.initials: AA
authors.lastname: Méthot
authors.forename: Alain
authors.initials: A
authors.lastname: Tapp
authors.forename: Falk
authors.initials: F
authors.lastname: Unger
mesh_terms: D003142:Communication; D008962:Models, Theoretical