Weak classicality in coupled N-level quantum systems
Department of Physics and Computer Science, Dayalbagh Educational Institute, Agra, Uttar Pradesh 282005, India
2 Department of Physics, Indian Institute of Technology Delhi, New Delhi 110016, India
Received in final form: 4 April 2019
Published online: 11 June 2019
The notion of “weak classical limit” for coupled N-level quantum systems as N → ∞ is introduced to understand the precise sense in which one attains classicality. There exists proofs that a system becomes classical at large N [1, 2]. On the other hand, it is known that non-locality and entanglement, the two hallmarks of non-classicality, thrive even as N → ∞. We reconcile these results in this paper by showing that so called classicality is not so much an inherent property of the system, as it is a consequence of limited experimental resources. Our focus is largely on non-locality, for which we study the Bell-CHSH and CGLMP inequalities for N-level systems.
Key words: Quantum Information
© EDP Sciences / Società Italiana di Fisica / Springer-Verlag GmbH Germany, part of Springer Nature, 2019