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The study of quantum correlations is central to quantum information and foundations. The paradigmatic case of Bell scenarios considers product measurements implemented on a multipartite state. The more general case of contextuality…

Quantum Physics · Physics 2025-09-24 Sujan V. K , Ravi Kunjwal

Nonlocality without entanglement is an interesting field. A manifestation of quantum nonlocality without entanglement is the local indistinguishability of a set of orthogonal product states. In this paper we analyze the character of…

Quantum Physics · Physics 2009-11-10 Ping Xing Chen , Cheng Zu Li

Nonlocality captures one of the counterintuitive features of nature that defies classical intuition. Recent investigations reveal that our physical world's nonlocality is at least tripartite; i.e., genuinely tripartite nonlocal correlations…

We show that universal quantum computation can be achieved in the standard pure-state circuit model while, at any time, the entanglement entropy of all bipartitions is small---even tending to zero with growing system size. The result is…

Quantum Physics · Physics 2013-04-11 Maarten Van den Nest

Any quantum system with a non-trivial Hamiltonian is able to simulate any other Hamiltonian evolution provided that a sufficiently large group of unitary control operations is available. We show that there exist finite groups with this…

Quantum Physics · Physics 2023-11-27 Pawel Wocjan , Martin Roetteler , Dominik Janzing , Thomas Beth

We generalize the classical notion of packing a set by balls with identical radii to the case where the radii may be different. The largest number of such balls that fit inside the set without overlapping is called its {\em non-uniform…

Metric Geometry · Mathematics 2020-08-05 Lee-Ad Gottlieb , Aryeh Kontorovich

Nonclassical properties of correlations-- like unpredictability, no-cloning and uncertainty-- are known to follow from two assumptions: nonlocality and no-signaling. For two-input-two-output correlations, we derive these properties from a…

Quantum Physics · Physics 2015-07-02 S. Aravinda , R. Srikanth

In quantum mechanics, nonlocality (a violation of a Bell inequality) is intimately linked to complementarity, by which we mean that consistently assigning values to different observables at the same time is not possible. Nonlocality can…

Quantum Physics · Physics 2012-02-02 Tobias Fritz

Understanding the relation between nonlocality and entanglement is one of the fundamental problems in quantum physics. In the bipartite case, it is known that the correlations observed for some entangled quantum states can be explained…

Quantum Physics · Physics 2015-07-22 R. Augusiak , M. Demianowicz , J. Tura , A. Acín

Bell inequality violations are often taken as evidence that quantum nonlocality guarantees intrinsic randomness, effectively playing the role of a "dice" at the heart of many device-independent cryptographic protocols. We show that there…

Quantum Physics · Physics 2025-09-11 Ravishankar Ramanathan , Yuan Liu , Stefano Pironio

So-called non-local boxes, which have been introduced as an idealization-in different respects-of the behavior of entangled quantum states, have been known to allow for unconditional bit commitment between the two involved parties. We show…

Quantum Physics · Physics 2010-12-14 Stefan Wolf , Juerg Wullschleger

Using the local geometrical properties of a given zero-dimensional square multivariate nonlinear system inside a box, we provide a simple but effective and new criterion for the uniqueness and the existence of a real simple zero of the…

Computational Geometry · Computer Science 2022-11-11 Jin-San Cheng , Junyi Wen

We show that non-local resources cannot be used for probabilistic signalling even if one can produce exact clones with the help of a probabilistic quantum cloning machine (PQCM). We show that PQCM cannot help to distinguish two statistical…

Quantum Physics · Physics 2009-10-31 Arun Kumar Pati

We discuss proofs of nonlocality based on a generalization by Erwin Schr\"odinger of the argument of Einstein, Podolsky and Rosen. These proofs do not appeal in any way to Bell's inequalities. Indeed, one striking feature of the proofs is…

Quantum Physics · Physics 2019-09-04 Jean Bricmont , Sheldon Goldstein , Douglas Hemmick

Quantum entanglement and nonlocality are inextricably linked. However, while entanglement is necessary for nonlocality, it is not always sufficient in the standard Bell scenario. We derive sufficient conditions for entanglement to give rise…

Quantum Physics · Physics 2021-02-22 Patricia Contreras-Tejada , Carlos Palazuelos , Julio I. de Vicente

We consider unambiguous discrimination of two separable bipartite states, one being pure and the other being a rank-2 mixed state. There is a gap between the optimal success probability under global measurements and the one achieved by…

Quantum Physics · Physics 2007-09-21 Masato Koashi , Fumitaka Takenaga , Takashi Yamamoto , Nobuyuki Imoto

In this paper, we discuss a generalization of log canonical singularities in the non-$\mathbb{Q}$-Gorenstein setting. We prove that if a normal complex projective variety has a non-invertible polarized endomorphism, then it has log…

Algebraic Geometry · Mathematics 2021-03-15 Shou Yoshikawa

We show that every infinite-dimensional Banach space with separable dual admits an equivalent norm which is weakly locally uniformly rotund but not locally uniformly rotund.

Functional Analysis · Mathematics 2015-12-03 Szymon Draga

Multi-party local quantum operations with shared quantum entanglement or shared classical randomness are studied. The following facts are established: (i) There is a ball of local operations with shared randomness lying within the space…

Quantum Physics · Physics 2013-10-16 Gus Gutoski

According to von Neumann, the global Hamiltonian of whole universe must be Hermitian in order to keep the eigenvalues real and to construct a self-consistent quantum theory. In addition to the open system approach by introducing…

Quantum Physics · Physics 2022-06-20 Minyi Huang , Ray-Kuang Lee