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Related papers: Quantum no-cloning theorem and entanglement

200 papers

The purposes of the present article are: a) To show that non-locality leads to the transfer of certain amounts of energy and angular momentum at very long distances, in an absolutely strange and unnatural manner, in any model reproducing…

General Physics · Physics 2007-10-05 Athanasios Prikas

Attempts at cloning a quantum system result in the introduction of imperfections in the state of the copies. This is a consequence of the no-cloning theorem, which is a fundamental law of quantum physics and the backbone of security for…

Quantum Physics · Physics 2016-08-17 Frédéric Bouchard , Robert Fickler , Robert W Boyd , Ebrahim Karimi

In this paper we present an approach to quantum cloning via free dynamical evolution of spin networks. By properly designing the network and the couplings between spins, we show that optimal 1->M phase covariant cloning can be achieved…

Quantum Physics · Physics 2007-05-23 Qing Chen , Jianhua Cheng , Ke-Lin Wang , Jiangfeng Du

We solve the generalised quantum Stein's lemma, proving that the Stein exponent associated with entanglement testing, namely, the quantum hypothesis testing task of distinguishing between $n$ copies of an entangled state $\rho_{AB}$ and a…

Quantum Physics · Physics 2025-07-28 Ludovico Lami

Quantum entanglement of identical particles is essential in quantum information theory. Yet, its correct determination remains an open issue hindering the general understanding and exploitation of many-particle systems. Operator-based…

Quantum Physics · Physics 2016-03-08 Rosario Lo Franco , Giuseppe Compagno

We consider the manipulation of multipartite entangled states in the limit of many copies under quantum operations that asymptotically cannot generate entanglement. As announced in [Brandao and Plenio, Nature Physics 4, 8 (2008)], and in…

Quantum Physics · Physics 2010-03-10 Fernando G. S. L. Brandao , Martin. B. Plenio

Given an arbitrary statistical theory, different from quantum mechanics, how to decide which are the nonclassical correlations? We present a formal framework which allows for a definition of nonclassical correlations in such theories,…

Quantum Physics · Physics 2016-11-26 F. Holik , C. Massri , A. Plastino

The quantum mechanics formalism introduced new revolutionary concepts challenging our everyday perceptions. Arguably, quantum entanglement, which explains correlations that cannot be reproduced classically, is the most notable of them.…

Quantum annealing leverages the properties of interacting quantum spin systems to solve computational problems, typically optimisation problems. Current hardware now has capabilities that can be used to solve condensed matter physics…

Quantum Physics · Physics 2026-04-09 Viv Kendon , Nicholas Chancellor

We present a discrete model theory similar in structure to ordinary quantum mechanics, but based on a finite field instead of complex amplitudes. The interpretation of this theory involves only the "modal" concepts of possibility and…

Quantum Physics · Physics 2011-08-02 Benjamin Schumacher , Michael D. Westmoreland

Entanglement is a fundamental feature of quantum theory as well as a key resource for quantum computing and quantum communication, but the entanglement mechanism has not been found at present. We think when the two subsystems exist…

Quantum Physics · Physics 2016-06-21 Xiang-Yao Wu , Xiao-Jing Liu , Jing-Bin Lu , Tian-Shun Li , Si-Qi Zhang , Yu Liang , Ji Ma , Hong Li

The problem of quantum state reduction in the process of measurement has attracted attention of almost everyone who created, developed or explained quantum physics to the students. Absence of a solution is the basis for the statement that…

Quantum Physics · Physics 2017-09-11 Constantin V. Usenko

The celebrated quantum no-cloning theorem states that an arbitrary quantum state cannot be cloned perfectly. This raises questions about cloning of classical states, which have also attracted attention. Here, we present a physical approach…

Quantum Physics · Physics 2020-11-25 Anirudh Reddy , Joseph Samuel , Supurna Sinha

We examine the inference of quantum density operators from incomplete information by means of the maximization of general non-additive entropic forms. Extended thermodynamic relations are given. When applied to a bipartite spin 1/2 system,…

Quantum Physics · Physics 2015-05-20 N. Canosa , R. Rossignoli

We propose that quantum entanglement is a special sort of selection artefact, explicable as a combination of (i) collider bias and (ii) a boundary constraint on the collider variable. We show that the proposal is valid for a special class…

Quantum Physics · Physics 2024-06-10 Huw Price , Ken Wharton

We consider the entanglement manipulation capabilities of the universal covariant quantum cloner or quantum processor circuit for quantum bits. We investigate its use for cloning a member of a bipartite or a genuine tripartite entangled…

Quantum Physics · Physics 2015-05-14 Levente Szabo , Matyas Koniorczyk , Peter Adam , Jozsef Janszky

In this paper, we study the entanglement and quantum discord of the output modes in the unified $1\rightarrow 2$ state-dependent cloning and probabilistic quantum cloning. The tripartite entanglement among the output modes and the quantum…

Quantum Physics · Physics 2015-06-23 Jun Zhang , Shao-xiong Wu , Chang-shui Yu

We study the properties of quantum information and quantum entanglement in moving frames. We show that the entanglement between the spins and the momenta of two particles can be interchanged under a Lorentz transformation, so that a pair of…

Quantum Physics · Physics 2007-05-23 Robert M. Gingrich , Christoph Adami

We introduce an approach to quantum cloning based on spin networks and we demonstrate that phase covariant cloning can be realized using no external control but only with a proper design of the Hamiltonian of the system. In the 1 -> 2…

Quantum Physics · Physics 2009-11-10 G. De Chiara , R. Fazio , C. Macchiavello , S. Montangero , G. M. Palma

A nonrelativistic proof of the spin-statistics theorem is given in terms of the field operators satisfying commutation and anticommutation relations, which are introduced here in the coordinate space as a means to build the permutation…

Quantum Physics · Physics 2025-12-16 Takafumi Kita