English
Related papers

Related papers: Causality and Cirel'son bounds

200 papers

Bell nonlocality and Einstein-Podolsky-Rosen (EPR) steering are every important quantum correlations of a composite quantum system. Bell nonlocality of a bipartite state is a quantum correlation demonstrated by some local quantum…

Quantum Physics · Physics 2018-01-31 Huaixin Cao , Zhihua Guo

We put forward a general classification for a structural description of the entanglement present in compound entities experimentally violating Bell's inequalities, making use of a new entanglement scheme that we developed recently. Our…

Artificial Intelligence · Computer Science 2015-12-31 Diederik Aerts , Sandro Sozzo

Simple quantitative measures of indeterminism and signalling, $I$ and $S$, are defined for models of statistical correlations. It is shown that any such model satisfies a generalised Bell-type inequality, with tight upper bound B(I,S). This…

Quantum Physics · Physics 2010-12-30 Michael J. W. Hall

Bell's theorem, stating that quantum predictions are incompatible with a local hidden variable description, is a cornerstone of quantum theory and at the center of many quantum information processing protocols. Over the years, different…

Quantum Physics · Physics 2020-05-27 I. S. Eliëns , S. G. A. Brito , R. Chaves

We have studied the possibility of post-quantum theories more nonlocal than the (standard) quantum theory using the modification of the quantum probability rule under the no-signaling condition. For this purpose we have considered the…

Quantum Physics · Physics 2012-08-15 Yeong Deok Han , Taeseung Choi

Unlike our basic theories of space and time, quantum mechanics is not a locally causal theory. Moreover, it is widely believed that any hopes of restoring local causality within a realistic theory have been undermined by Bell's theorem and…

Quantum Physics · Physics 2012-05-03 Joy Christian

Bell nonlocality describes a manifestation of quantum mechanics that cannot be explained by any local hidden variable model. Its origin lies in the nature of quantum entanglement, although understanding the precise relationship between…

Quantum Physics · Physics 2022-01-03 Kuntal Sengupta , Rana Zibakhsh , Eric Chitambar , Gilad Gour

We in this Letter derive analytic formulas of Bell correlations in terms of quantum probability statistics under the assumption of measuring outcome-independence. For a spin-1/2 singlet state we find analytically that the violations of…

Quantum Physics · Physics 2013-04-09 Zhigang Song , J. -Q. Liang , L. -F. Wei

Einstein-Podolsky-Rosen (EPR) steering is an intermediate quantum correlation that lies in between entanglement and Bell non-locality. Its temporal analogue, temporal steering, has recently been shown to have applications in quantum…

Quantum Physics · Physics 2018-08-07 Huan-Yu Ku , Shin-Liang Chen , Neill Lambert , Yueh-Nan Chen , Franco Nori

This work aims at exploring whether the nonlocal correlations due to quantum entanglement could exist without nonlocal causation. This is done with the aid of a toy model to investigate whether the ability of two quantum entangled particles…

General Physics · Physics 2025-03-25 Marco Pettini

Bell nonlocality exemplifies the most profound departure of quantum theory from classical realism. Yet, the extent of nonlocality in quantum theory is intrinsically bounded, falling short of the correlations permitted by the relativistic…

A classical fluid splitter produces the same patterns of energy redistribution as a Stern-Gerlach quantum device, with rotationally invariant coefficients of correlation between molecular paths. Alternative settings express a cosine squared…

General Physics · Physics 2026-04-23 Ghenadie N. Mardari

Since Bell's theorem, it is known that the concept of local realism fails to explain quantum phenomena. Indeed, the violation of a Bell inequality has become a synonym of the incompatibility of quantum theory with our classical notion of…

Simulation tasks are insightful tools to compare information-theoretic resources. Considering a generalization of usual Bell scenarios where external quantum inputs are provided to the parties, we show that any entangled quantum state…

Quantum Physics · Physics 2013-06-06 Denis Rosset , Cyril Branciard , Nicolas Gisin , Yeong-Cherng Liang

We show that correlations inconsistent with any locally causal description can be a generic feature of measurements on entangled quantum states. Specifically, spatially-separated parties who perform local measurements on a…

Quantum Physics · Physics 2016-09-08 Yeong-Cherng Liang , Nicholas Harrigan , Stephen D. Bartlett , Terry Rudolph

Non-locality without inequality is an elegant argument introduced by L. Hardy for two qubit systems, and later generalised to $n$ qubits, to establish contradiction of quantum theory with local realism. Interestingly, for $n=2$ this…

Quantum Physics · Physics 2015-05-19 Sibasish Ghosh , Shasanka Mohan Roy

Bell's theorem guarantees that no model based on local variables can reproduce quantum correlations. Also some models based on non-local variables, if subject to apparently "reasonable" constraints, may fail to reproduce quantum physics. In…

We give a set of necessary conditions for locality in bipartite systems, which include and generalize known Bell's inequalities. Each condition corresponds to a specific order of the expansion of random variables defined on graphs, in terms…

The non-local nature of the correlations possessed by quantum systems may be revealed by experimental demonstrations of the violation of Bell-type inequalities. Recent work has placed bounds on the correlations that quantum systems can…

Quantum Physics · Physics 2020-08-19 Amandeep Singh , Dileep Singh , Vaishali Gulati , Arvind , Kavita Dorai

Quantum entanglement plays a fundamental role in quantum cryptography and computation. An important example of quantum entanglement can be found in the correlations of Einstein, Podolsky, and Rosen (EPR). However, despite the plethora of…

Quantum Physics · Physics 2026-04-07 Luiz Carlos Ryff