ترغب بنشر مسار تعليمي؟ اضغط هنا

Two faced Janus of quantum nonlocality

34   0   0.0 ( 0 )
 نشر من قبل Andrei Khrennikov Yu
 تاريخ النشر 2020
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Andrei Khrennikov




اسأل ChatGPT حول البحث

This paper is a new step towards getting rid of nonlocality from quantum physics. This is an attempt to structure the nonlocality mess. Quantum nonlocality is Janus faced. One its face is projection (Einstein-Luders) nonlocality and another Bell nonlocality. The first one is genuine quantum nonlocality, the second one is subquantum nonlocality. Recently it was shown that Bell nonlocality is a simple consequence of the complementarity principle. We now show that projection nonlocality has no connection with physical space. Projection state update is generalization of the well known operation of probability update used in classical inference. We elevate the role of interpretations of a quantum state. By using the individual (physical) interpretation, one can really get the illusion of a spooky action at a distance resulting from Luders state update. The statistical interpretation combined with treating the quantum formalism as machinery for update of probability is known as the Vaxjo interpretation. Here one follows the standard scheme of probability update adjusted to the quantum calculus of probability. The latter is based on operating with states represented by vectors (or density operators). We present in parallel classical and quantum probability updates. From this presentation, it is clear that both classical and quantum faster-than-light change of statistical correlation take place in mental and not physical space.

قيم البحث

اقرأ أيضاً

What violations of Bell inequalities teach us is that the world is quantum mechanical, i.e., nonclassical. Assertions that they imply the world is nonlocal arise from ignoring differences between quantum and classical physics.
41 - Moses Fayngold 2018
Detailed analysis of behavior of spin-entangled particle pairs under arbitrary rotations in their Hilbert space has been performed. It shows a rich range of varieties (faces) of entanglement in different bases. Analytic criteria are obtained for the respective faces of an entangled state. The corresponding conditions generally depend on both the state itself and the chosen basis. The most important result is revealing a deep analogy between a spin-entangled electronic qubit pair and momentum-entangled photon pair. Both cases exhibit coherence transfer from individual particles to nonlocal state of the system. This analogy allows us to predict certain features of the interference patterns in spin-entangled qubit pairs.
We show that for all $nge3$, an example of an $n$-partite quantum correlation that is not genuinely multipartite nonlocal but rather exhibiting anonymous nonlocality, that is, nonlocal but biseparable with respect to all bipartitions, can be obtained by locally measuring the $n$-partite Greenberger-Horne-Zeilinger (GHZ) state. This anonymity is a manifestation of the impossibility to attribute unambiguously the underlying multipartite nonlocality to any definite subset(s) of the parties, even though the correlation can indeed be produced by nonlocal collaboration involving only such subsets. An explicit biseparable decomposition of these correlations is provided for any partitioning of the $n$ parties into two groups. Two possible applications of these anonymous GHZ correlations in the device-independent setting are discussed: multipartite secret sharing between any two groups of parties and bipartite quantum key distribution that is robust against nearly arbitrary leakage of information.
74 - Ming-Xing Luo 2018
The multipartite correlations derived from local measurements on some composite quantum systems are inconsistent with those reproduced classically. This inconsistency is known as quantum nonlocality and shows a milestone in the foundations of quantum theory. Still, it is NP hard to decide a nonlocal quantum state. We investigate an extended question: how to characterize the nonlocal properties of quantum states that are distributed and measured in networks. We first prove the generic tripartite nonlocality of chain-shaped quantum networks using semiquantum nonlocal games. We then introduce a new approach to prove the generic activated nonlocality as a result of entanglement swapping for all bipartite entangled states. The result is further applied to show the multipartite nonlocality and activated nonlocality for all nontrivial quantum networks consisting of any entangled states. Our results provide the nonlocality witnesses and quantum superiorities of all connected quantum networks or nontrivial hybrid networks in contrast to classical networks.
The results of local measurements on some composite quantum systems cannot be reproduced classically. This impossibility, known as quantum nonlocality, represents a milestone in the foundations of quantum theory. Quantum nonlocality is also a valuabl e resource for information processing tasks, e.g. quantum communication, quantum key distribution, quantum state estimation, or randomness extraction. Still, deciding if a quantum state is nonlocal remains a challenging problem. Here we introduce a novel approach to this question: we study the nonlocal properties of quantum states when distributed and measured in networks. Using our framework, we show how any one-way entanglement distillable state leads to nonlocal correlations. Then, we prove that nonlocality is a non-additive resource, which can be activated. There exist states, local at the single-copy level, that become nonlocal when taking several copies of it. Our results imply that the nonlocality of quantum states strongly depends on the measurement context.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا