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Related papers: Contextual advantage for state-dependent cloning

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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

We study the problem of universal quantum cloning -- taking several identical copies of a pure but unknown quantum state and producing further copies. While it is well known that it is impossible to perfectly reproduce the state, how well…

Quantum Physics · Physics 2016-08-09 Alastair Kay

According to a recent no-go theorem (M. Pusey, J. Barrett and T. Rudolph, Nature Physics 8, 475 (2012)), models in which quantum states correspond to probability distributions over the values of some underlying physical variables must have…

Quantum Physics · Physics 2014-07-02 Jonathan Barrett , Eric G. Cavalcanti , Raymond Lal , Owen J. E. Maroney

In the framework of certain general probability theories of single systems, we identify various nonclassical features such as incompatibility, multiple pure-state decomposability, measurement disturbance, no-cloning and the impossibility of…

Quantum Physics · Physics 2022-06-10 S. Aravinda , R. Srikanth , Anirban Pathak

The famous no-cloning principle has been shown recently to enable a number of uncloneable functionalities. Here we address for the first time unkeyed quantum uncloneablity, via the study of a complexity-theoretic tool that enables a…

Quantum Physics · Physics 2024-10-14 Anne Broadbent , Martti Karvonen , Sébastien Lord

Contextuality is a key characteristic that separates quantum from classical phenomena and an important tool in understanding the potential advantage of quantum computation. However, when assessing the quantum resources available for quantum…

Quantum Physics · Physics 2026-03-04 Maiyuren Srikumar , Stephen D. Bartlett , Angela Karanjai

Contextuality and nonlocality are non-classical properties exhibited by quantum statistics whose implications profoundly impact both foundations and applications of quantum theory. In this paper we provide some insights into logical…

Quantum Physics · Physics 2021-08-11 Leonardo Santos , Barbara Amaral

The existence of incompatible measurements is often believed to be a feature of quantum theory which signals its inconsistency with any classical worldview. To prove the failure of classicality in the sense of Kochen-Specker…

Quantum Physics · Physics 2024-04-05 John H. Selby , David Schmid , Elie Wolfe , Ana Belén Sainz , Ravi Kunjwal , Robert W. Spekkens

Quantum theory features several phenomena which can be considered as resources for information processing tasks. Some of these effects, such as entanglement, arise in a nonlocal scenario, where a quantum state is distributed between…

Quantum Physics · Physics 2024-07-22 Martin Plávala , Otfried Gühne

We study quantum states produced by optimal phase covariant quantum cloners. We argue that cloned quantum superpositions are not macroscopic superpositions in the spirit of Schr\"odinger's cat, despite their large particle number. This is…

Quantum Physics · Physics 2012-10-26 F. Fröwis , W. Dür

The question of whether quantum phenomena can be explained by classical models with hidden variables is the subject of a long lasting debate. In 1964, Bell showed that certain types of classical models cannot explain the quantum mechanical…

Quantum Physics · Physics 2009-07-21 G. Kirchmair , F. Zähringer , R. Gerritsma , M. Kleinmann , O. Gühne , A. Cabello , R. Blatt , C. F. Roos

Nonlinear modifications of quantum theory are considered potential candidates for the theory of quantum gravity, with the intuitive argument that since Einstein field equations are nonlinear, quantum gravity should be nonlinear as well.…

Quantum Physics · Physics 2025-06-06 Ruben Campos Delgado , Martin Plávala

We investigate the connection between quantum no-cloning theorem and Bell's theorem. Designing some Bell's inequalities, we show that quantum no-cloning theorem can always be certified by Bell's theorem, and this fact in turn reflects that…

Quantum Physics · Physics 2015-03-19 Jing-Ling Chen , Hong-Yi Su , Chunfeng Wu , Xiang-Jun Ye , Dong-Ling Deng , C. H. Oh

It is well known that in quantum mechanics we cannot always define consistently properties that are context independent. Many approaches exist to describe contextual properties, such as Contextuality by Default (CbD), sheaf theory, topos…

Quantum Physics · Physics 2017-07-18 J. Acacio de Barros , Federico Holik , Decio Krause

We derive the transformation for the optimal universal quantum anti-cloner which produces two anti-parallel outputs for a single input state. The fidelity is shown to be 2/3 which is same as the measurement fidelity. We consider a…

Quantum Physics · Physics 2007-05-23 David D. Song , Lucien Hardy

Nonclassicality, defined in the quantum optical sense, serves as a resource for photon-based quantum technologies. Therefore, certifying the nonclassicality of a quantum state is crucial for gauging its potential for quantum advantage.…

Non-classical probability (along with its underlying logic) is a defining feature of quantum mechanics. A formulation that incorporates them, inherently and directly, would promise a unified description of seemingly different prescriptions…

Quantum Physics · Physics 2019-05-21 Soumik Adhikary , Sooryansh Asthana , V. Ravishankar

By relevant modifications, the known global-fidelity limits of state-dependent cloning are extended to mixed quantum states. We assume that the ancilla contains some a priori information about the input state. As it is shown, the obtained…

Quantum Physics · Physics 2009-11-10 Alexey E. Rastegin

We show that there are Bell-type inequalities for noncontextual theories that are violated by any quantum state. One of these inequalities between the correlations of compatible measurements is particularly suitable for testing this…

Quantum Physics · Physics 2009-07-28 Adan Cabello

In order to claim that one has experimentally tested whether a noncontextual ontological model could underlie certain measurement statistics in quantum theory, it is necessary to have a notion of noncontextuality that applies to unsharp…

Quantum Physics · Physics 2015-01-07 Robert W. Spekkens