English

A unified framework for Bell inequalities from continuous-variable contextuality

Quantum Physics 2026-01-13 v1

Abstract

Although the original EPR paradox was formulated in terms of position and momentum, most studies of these phenomena have focused on measurement scenarios with only a discrete number of possible measurement outcomes. Here, we present a framework for studying non-locality that is agnostic to the dimension of the physical systems involved, allowing us to probe purely continuous-variable, discrete-variable, or hybrid non-locality. Our approach allows us to find the optimal Bell inequality for any given measurement scenario and quantifies the amount of non-locality that is present in measurement statistics. This formalism unifies the existing literature on continuous-variable non-locality and allows us to identify new states in which Bell non-locality can be probed through homodyne detection. Notably, we find the first example of continuous-variable non-locality that cannot be mapped to a CHSH Bell inequality. Moreover, we provide several examples of simple hybrid DV-CV entangled states that could lead to near-term violation of Bell inequalities.

Keywords

Cite

@article{arxiv.2601.07686,
  title  = {A unified framework for Bell inequalities from continuous-variable contextuality},
  author = {Carlos Ernesto Lopetegui-González and Gaël Massé and Enky Oudot and Uta Isabella Meyer and Federico Centrone and Frédéric Grosshans and Pierre-Emmanuel Emeriau and Ulysse Chabaud and Mattia Walschaers},
  journal= {arXiv preprint arXiv:2601.07686},
  year   = {2026}
}

Comments

17 pages, 14 figures. Comments welcome!

R2 v1 2026-07-01T09:00:59.737Z