Quantum Entanglement and Nonlocality

Tan Hui-zhao

The quantum entanglement and nonlocality,the most miraculous feature and resource of quantum information,do not only involve basic problems of quantum theory such as reality,locality,latent variable and measurement theory,but pose a fundamental question for philosophy.With a philosophical reflection on quantum entanglement and nonlocality,the paper discusses the philosophical significance of quantum entanglement and nonlocality.It bears an important significance for recognizing and understanding the information theory and technology.

Jordi Tura i Brugués

Geoff J. Pryde, Jeremy L. O’Brien, Stephen D. Bartlett +1 more

Ya Xi, Tinggui Zhang, Zhu‐Jun Zheng +2 more

We study the relations between quantum coherence and quantum nonlocality, genuine quantum entanglement, and genuine quantum nonlocality. We show that the coherence of a qubit state can be converted to the nonlocality of two-qubit states via incoherent operations. The results are also generalized to the qudit case. Furthermore, rigorous relations between the quantum coherence of a single-partite state and the genuine multipartite quantum entanglement, as well as the genuine three-qubit quantum nonlocality, are established.

Wu, Xiaohua

Andrés Ducuara, Javier Madroñero, John Henry Reina

Quantum nonlocality is a cornerstone property for the development of the socalled quantum protocols as well as for the characterisation, and possible generalisation of quantum theory. However, there are still fundamental aspects of this property that need to be addressed; in particular, its relation with the property of quantum entanglement. It is well known that every nonlocal state is an entangled one, yet there exist entangled local states. Therefore, within their original defnitions, these two properties are not equivalent. The study of this relationship has been put forward by means of the generalisation of nonlocality through the so-called activation of nonlocality scenarios. The idea is to only work with these entangled local states in order to try to recover (activate) nonlocality. In this Thesis, we have numerically addressed the properties of entanglement, nonlocality (mostly by means of the violation of the CHSH-inequality), as well as the following generalisations of nonlocality: k-copy nonlocality, hidden nonlocality, and the combination of these two scenarios, namely, hidden k-copy nonlocality and tensor/filter activation of hidden nonlocality. We have studied these properties for some bipartite entangled local states, and some two-qubit not CHSH-inequality violating states of interest. In particular, we have analysed these properties for two-qubit states that come from the study of quantum games' strategies and the dynamics of open quantum systems.