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Related papers: Contextuality of all optimal quantum cloning

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We report a method that exploits a connection between quantum contextuality and graph theory to reveal any form of quantum contextuality in high-precision experiments. We use this technique to identify a graph which corresponds to an…

I assess various proposals for the source of the intuition that there is something problematic about contextuality, ultimately concluding that contextuality is best thought of in terms of fine-tuning. I then argue that as with other…

Quantum Physics · Physics 2021-11-24 Emily Adlam

Quantum theory departs from classical probabilistic theories in foundational ways. These departures--termed quantumness here--power quantum information and computation. This thesis charts the role of discrete structures in assessing…

Quantum Physics · Physics 2025-12-22 Ravi Kunjwal

Generalized contextuality is a hallmark of nonclassical theories like quantum mechanics. Yet, three fundamental computational problems concerning its decidability and complexity remain open. First, determining the complexity of deciding if…

Quantum Physics · Physics 2025-06-12 Theodoros Yianni , Farid Shahandeh

Contextuality is a particular quantum phenomenon that has no analogue in classical probability theory. Given two independent systems, a natural question is how to represent such a situation as a single test space. In other words, how…

Quantum Physics · Physics 2018-12-24 Ana Belén Sainz , Elie Wolfe

Quantum advantage is notoriously hard to find and even harder to prove. For example the class of functions computable with classical physics actually exactly coincides with the class computable quantum-mechanically. It is strongly believed,…

Quantum Physics · Physics 2015-10-07 Howard Dale , David Jennings , Terry Rudolph

We describe a scheme of quantum computation with magic states on qubits for which contextuality is a necessary resource possessed by the magic states. More generally, we establish contextuality as a necessary resource for all schemes of…

Quantum Physics · Physics 2017-06-27 Robert Raussendorf , Dan E. Browne , Nicolas Delfosse , Cihan Okay , Juan Bermejo-Vega

Contextuality is a fundamental property of quantum mechanics. Contrary to entanglement, which can only exist in composite systems, contextuality is also present for single entities. The case of a three-level system is of particular interest…

High Energy Physics - Phenomenology · Physics 2025-03-20 M. Fabbrichesi , R. Floreanini , E. Gabrielli , L. Marzola

Motivated by notions of quantum heuristics and by average-case rather than worst-case algorithmic analysis, we define quantum computational advantage in terms of individual problem instances. Inspired by the classical notions of Kolmogorov…

Quantum Physics · Physics 2025-10-03 Harry Buhrman , Niklas Galke , Konstantinos Meichanetzidis

Quantum computing provides computational advantages in various domains. To benefit from these advantages complex hybrid quantum applications must be built, which comprise both quantum and classical programs. Engineering these applications…

Quantum contextuality in systems of identical bosonic particles is explicitly exhibited via the maximum violation of a suitable inequality of Clauser-Horne-Shimony-Holt type. Unlike the approaches considered so far, which make use of…

Quantum Physics · Physics 2015-05-30 F. Benatti , R. Floreanini , M. Genovese , S. Olivares

Contextuality can be understood as the impossibility to construct a globally consistent description of a model even if there is local agreement. In particular, quantum models present this property. We can describe contextuality with the…

Quantum Physics · Physics 2024-07-04 Sidiney B. Montanhano

The impossibility of perfectly copying (or cloning) an arbitrary quantum state is one of the basic rules governing the physics of quantum systems. The processes that perform the optimal approximate cloning have been found in many cases.…

Quantum Physics · Physics 2009-11-11 Valerio Scarani , Sofyan Iblisdir , Nicolas Gisin , Antonio Acin

A generalisation of quantum contextuality to the case of many indentical particles is presented. The model consists of a finite collection of modes that can be occupied by N particles, either bosons or fermions. Measurement scenarios allow…

Quantum Physics · Physics 2017-02-01 Pawel Kurzynski

Classical chaos is marked by an extreme sensitivity to initial conditions, where infinitesimally close trajectories separate exponentially over time. In quantum mechanics, however, unitary evolution and the uncertainty principle preclude…

Quantum Physics · Physics 2025-03-19 Sanchit Srivastava , Shohini Ghose

Contextuality is a central property in comparative analysis of classical, quantum, and supercorrelated systems. We examine and compare two well-motivated approaches to contextuality. One approach ("contextuality-by-default") is based on the…

Quantum Physics · Physics 2016-01-21 J. Acacio de Barros , Ehtibar N. Dzhafarov , Janne V. Kujala , Gary Oas

Homomorphisms between relational structures play a central role in finite model theory, constraint satisfaction and database theory. A central theme in quantum computation is to show how quantum resources can be used to gain advantage in…

Logic in Computer Science · Computer Science 2021-03-09 Samson Abramsky , Rui Soares Barbosa , Nadish de Silva , Octavio Zapata

Generalized contextuality is a resource for a wide range of communication and information processing protocols. However, contextuality is not possible without coherence, and so can be destroyed by dephasing noise. Here, we explore the…

Quantum Physics · Physics 2024-04-05 Vinicius P. Rossi , David Schmid , John H. Selby , Ana Belén Sainz

Sharing correlated random variables is a resource for a number of information theoretic tasks such as privacy amplification, simultaneous message passing, secret sharing and many more. In this article, we show that to establish such a…

Quantum Physics · Physics 2021-11-03 Tamal Guha , Mir Alimuddin , Sumit Rout , Amit Mukherjee , Some Sankar Bhattacharya , Manik Banik

The simulation of quantum effects requires certain classical resources, and quantifying them is an important step in order to characterize the difference between quantum and classical physics. For a simulation of the phenomenon of…

Quantum Physics · Physics 2011-11-10 Matthias Kleinmann , Otfried Gühne , José R. Portillo , Jan-Åke Larsson , Adán Cabello