VCQ talk by Adán Cabello (Universidad de Sevilla)

on "Bell nonlocality and Kochen-Specker contextuality: How are they connected?"

VCQ COLLOQUIUM TALK

 

by

Adán Cabello

(Universidad de Sevilla)

 

MONDAY, April 12th, starting at 17:00

 

Bell nonlocality and Kochen-Specker contextuality: How are they connected?

 

Bell nonlocality and Kochen-Specker (KS) contextuality are logically independent concepts, fuel different protocols with quantum advantage, and have distinct classical simulation costs. A natural question is what are the relations between these concepts, advantages, and costs. To address this question, it would be useful to have a map that captures all the connections between Bell nonlocality and KS contextuality in quantum theory. Here, we introduce such a map. After defining the theory-independent notions of Bell nonlocality and KS contextuality for ideal measurements, we point out that, in quantum theory, due to Neumark's dilation theorem, every matrix of quantum Bell nonlocal correlations can be mapped to an identical matrix of KS contextual correlations. A more difficult problem is identifying connections from KS contextuality into Bell nonlocality. We show that there are "one-to-one'' and partial connections for some KS contextuality scenarios, but not for all of them. However, we also present a method that transforms any matrix of KS contextual correlations into a matrix of Bell nonlocal correlations.

 

Host: Anton Zeilinger

 

Further information can be found on the VCQ website: 

https://vcq.quantum.at/colloquium-ss21/