An elegant scheme of self-testing for multipartite Bell inequalities

Date: Thursday, November 10, 2022
Time: 12:00
Location: ICTQT, room 317
Passcode: 743020
seminar

Speaker: Ekta Panwar (UG/ICTQT)

Abstract The predictions of quantum theory are incompatible with local-causal explanations. This phenomenon is called Bell non-locality and is witnessed by the violation of Bell-inequalities. The maximal violation of certain Bell-inequalities can only be attained in an essentially unique manner. This feature is referred to as self-testing and constitutes the most accurate form of certification of quantum devices. While self-testing in bipartite Bell scenarios has been thoroughly studied, self-testing in the more complex multipartite Bell scenarios remains largely unexplored. This work presents a simple and broadly applicable self-testing argument for N-partite correlation Bell inequalities with two binary outcome observables per party. Our proof technique forms a generalization of the Mayer-Yao formulation and is not restricted to linear Bell-inequalities, unlike the usual sum of squares method. To showcase the versatility of our proof technique, we obtain self-testing statements for N party Mermin-Ardehali-Belinskii-Klyshko (MABK) and Werner-Wolf-Weinfurter-Zukowski-Brukner (WWWZB) family of linear Bell inequalities, Uffink’s family of N party quadratic Bell-inequalities, and the novel Uffink’s complex-valued N partite Bell expressions.