Bell's Inequalities - Foundations and Quantum Communication
- Author(s)
- Caslav Brukner, Marek Zukowski
- Abstract
Efforts to construct deeper, realistic, level of physical description, in which individual systems have, like in classical physics, preexisting properties revealed by measurements are known as hidden-variable programs. Demonstrations that a hidden-variable program necessarily requires outcomes of certain experiments to disagree with the predictions of quantum theory are called "no-go theorems". The Bell theorem excludes local hidden variable theories. The Kochen-Specker theorem excludes noncontextual hidden variable theories. In local hidden-variable theories faster-that-light-influences are forbidden, thus the results for a given measurement (actual, or just potentially possible) are independent of the settings of other measurement devices which are at space-like separation. In noncontextual hidden-variable theories the predetermined results of a (degenerate) observable are independent of any other observables that are measured jointly with it. It is a fundamental doctrine of quantum information science that quantum communication and quantum computation outperforms their classical counterparts. If this is to be true, some fundamental quantum characteristics must be behind better-than-classical performance of information processing tasks. This chapter aims at establishing connections between certain quantum information protocols and foundational issues in quantum theory. After a brief discusion of the most common misinterpretations of Bell's theorem and a discussion of what its real meaning is, it will be demonstrated how quantum contextuality and violations of local realism can be used as useful resources in quantum information applications.
- Organisation(s)
- Quantum Optics, Quantum Nanophysics and Quantum Information
- Pages
- 1413-1450
- No. of pages
- 38
- DOI
- https://doi.org/10.1007/978-3-540-92910-9_42
- Publication date
- 2012
- Austrian Fields of Science 2012
- 103026 Quantum optics
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/8fdaa162-c635-45d4-ad9f-0eb026533d12