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Related papers: Weak measurements and supraluminal communication

200 papers

Dense coding is the seminal example of how entanglement can boost qubit communication, from sending one bit to sending two bits. This is made possible by projecting separate particles onto a maximally entangled basis. We investigate more…

In this paper we propose a setup for the weak measurement of photon arrival time. It is found that the weak values of this arrival time can lie far away from the expectation value, and in principle also in regions forbidden by special…

Quantum Physics · Physics 2009-11-10 S. E. Ahnert , M. C. Payne

A large literature has grown up around the proposed use of 'weak measurements' (i.e., unsharp measurements followed by post-selection) to allegedly provide information about hidden ontological features of quantum systems. This paper…

Quantum Physics · Physics 2017-05-16 R. E. Kastner

We show how one can measure the signal from slow jumps of a single molecule between metastable positions using a setup where the molecule is fixed to one lead, and one of the coupling strengths is controlled externally. Such a measurement…

Mesoscale and Nanoscale Physics · Physics 2013-04-04 Tero T. Heikkila , Wolfgang Belzig

We consider a thought experiment where the preparation of a macroscopically massive or charged particle in a quantum superposition and the associated dynamics of a distant test particle apparently allow for superluminal communication. We…

Quantum Physics · Physics 2016-03-10 Andrea Mari , Giacomo De Palma , Vittorio Giovannetti

In a recent paper, A.Y. Shiekh has discussed an experimental set-up which, in his opinion, should make possible faster-than-light communication using the collapse of the quantum wave function. Contrary to the many proposals which have been…

Quantum Physics · Physics 2009-11-13 A. Bassi , G. C. Ghirardi

Weak amplification is a signal enhancement technique which is used to measure tiny changes that otherwise cannot be determined because of technical limitations. It is based on the existence of a special type of interaction which couples a…

Quantum Physics · Physics 2015-06-04 Juan P. Torres , Graciana Puentes , Nathaniel Hermosa , Luis Jose Salazar-Serrano

Traditionally, quantum state correlation can be obtained with calculations on a state density matrix already known. Here, we propose a model with which correlations of unknown quantum states can be obtained. There are no needs of classical…

Quantum Physics · Physics 2018-06-18 Hui Li , Yan-Song Li , Chao Zheng , Xian Lu

Nonlocality plays a fundamental role in quantum information science. Recently, it has been theoretically predicted and experimentally demonstrated that the nonlocality of an entangled pair may be shared among multiple observers using weak…

Quantum Physics · Physics 2020-10-06 Tianfeng Feng , Changliang Ren , Yuling Tian , Maolin Luo , Haofei Shi , Jingling Chen , Xiaoqi Zhou

An EPR experiment with polarized entangled photons is performed to test the Eberhard model. According to the Eberhard model, quantum correlations between space-like separated events are due to a superluminal communication signal propagating…

Quantum Physics · Physics 2011-01-11 Bruno Cocciaro , Sandro Faetti , Leone Fronzoni

Quantum nonlocality offers a secure way to produce random numbers: their unpredictability is intrinsic and can be certified just by observing the statistic of the measurement outcomes, without assumptions on how they are produced. To do…

We show that controlled interference of a particle's wavefunction can be used to perform a quantum mechanical measurement in an incomplete basis. This happens because the measurement projects the particle into a lower dimensional subspace…

Quantum Physics · Physics 2007-05-23 R. Srikanth

Recent empirical work in the field of 'weak measurements' has yielded novel ways of more directly accessing and exploring the quantum wavefunction. Measuring either position or momentum for a photon in a 'weak' manner yields a wide range of…

Quantum Physics · Physics 2013-06-17 David R Geelan

The notion of weak measurement provides a formalism for extracting information from a quantum system in the limit of vanishing disturbance to its state. Here we extend this formalism to the measurement of sequences of observables. When…

Quantum Physics · Physics 2009-11-13 Graeme Mitchison , Richard Jozsa , Sandu Popescu

In this paper we study the correlations that arise when two separated parties perform measurements on systems they hold locally. We restrict ourselves to those correlations with which arbitrarily fast transmission of information is…

Quantum Physics · Physics 2009-11-11 Nick S. Jones , Lluis Masanes

Complete measurements, while providing maximal information gain, results in destruction of the shared entanglement. In the standard teleportation scheme, the sender's measurement on the shared entangled state between the sender and the…

Quantum Physics · Physics 2022-02-22 Saptarshi Roy , Anindita Bera , Shiladitya Mal , Aditi Sen De , Ujjwal Sen

We search a simplest and minimal way to determine whether a given quantum system is entangled or separable. For this end, we propose binary correlation measurements in which restricted knowledge of only zero or non-zero correlations is…

Quantum Physics · Physics 2021-06-29 Toru Ohira

The possibility of recovering and protecting the entanglement of accelerated 2-qubit and 2-qutrit systems is discussed using weak-reverse measurements. The accelerated partial entangled states are more responsive to be protected than the…

Quantum Physics · Physics 2017-03-27 Nasser Metwally

The fact that not all quantum observables are jointly measurable is one of the major differences between quantum and classical theory. In the former, non-commuting observables can only be simultaneously measured with limited precision. We…

Quantum Physics · Physics 2016-10-17 Gilles Pütz , Tomer Barnea , Nicolas Gisin , Anthony Martin

We study when a physical operation can produce entanglement between two systems initially disentangled. The formalism we develop allows to show that one can perform certain non-local operations with unit probability by performing local…

Quantum Physics · Physics 2009-11-06 J. I. Cirac , W. Dür , B. Kraus , M. Lewenstein