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Related papers: Weak Measurements and Counterfactual Computation

200 papers

We propose to use weak measurements away from the weak-value amplification regime to carry out precision measurements of time delays of light. Our scheme is robust to several sources of noise that are shown to only limit the relative…

Quantum Physics · Physics 2013-02-27 Grégory Strübi , C. Bruder

We propose a usage of a weak value for a quantum processing between preselection and postselection. While the weak value of a projector of 1 provides a process with certainty like the probability of 1, the weak value of -1 negates the…

Quantum Physics · Physics 2018-07-03 Kazuhiro Yokota , Nobuyuki Imoto

We re-examine the status of the weak value of a quantum mechanical observable as an objective physical concept, addressing its physical interpretation and general domain of applicability. We show that the weak value can be regarded as a…

Quantum Physics · Physics 2007-05-23 Yakir Aharonov , Alonso Botero

Recently, weak measurements have attracted a lot of interest as an experimental method for the investigation of non-classical correlations between observables that cannot be measured jointly. Here, I explain how the complex valued…

Quantum Physics · Physics 2013-05-02 Holger F. Hofmann

We present a scheme to estimate Gaussian states of one-dimensional continuous variable systems, based on weak (unsharp) quantum measurements. The estimation of a Gaussian state requires us to find position ($q$), momentum ($p$) and their…

Quantum Physics · Physics 2017-04-05 Debmalya Das , Arvind

Classical-realistic analysis of entangled systems have lead to retrodiction paradoxes, which ordinarily have been dismissed on the grounds of counter-factuality. Instead, we claim that such paradoxes point to a deeper logical structure…

Quantum Physics · Physics 2015-06-26 Yakir Aharonov , Alonso Botero , Sandu Popescu , Benni Reznik , Jeff Tollaksen

The quantum weak value draws many attentions recently from theoretical curiosity to experimental applications. Now we design an unusual weak measuring procedure as the pre-selection, mid-selection and post-selection to study the correlation…

Quantum Physics · Physics 2017-03-01 Yiming Pan

The relationship between the real part of the weak value of the momentum operator at a post selected position is discussed and the meaning of the experimentally determined stream-lines in the Toronto experiment of Kocsis {\em et al} is…

Quantum Physics · Physics 2014-08-26 R. Flack , B. J. Hiley

The adoption of increasingly complex deep models has fueled an urgent need for insight into how these models make predictions. Counterfactual explanations form a powerful tool for providing actionable explanations to practitioners.…

Machine Learning · Computer Science 2024-11-05 Paraskevas Pegios , Aasa Feragen , Andreas Abildtrup Hansen , Georgios Arvanitidis

The quantum measurement procedure based on the Lorentz transformation formalism and weak perturbation of the system is considered. In the simple case of a single-qubit it turns out that one can perform 4-dimension pseudo-rotation along with…

Quantum Physics · Physics 2019-06-18 Yu. I. Bogdanova , N. A. Bogdanova , B. I. Bantysh , Yu. A. Kuznetsov

We refute the widely held belief that the quantum weak value necessarily pertains to weak measurements. To accomplish this, we use the transverse position of a beam as the detector for the conditioned von Neumann measurement of a system…

Quantum Physics · Physics 2013-01-16 J. Dressel , A. N. Jordan

In this study we critically examine some important papers on weak measurement and weak values. We find some insufficiency and mistakes in these papers, and we demonstrate that the real parts of weak values provide the back-action to the…

Quantum Physics · Physics 2015-04-20 Riuji Mochizuki

It is well known that the quantum Zeno effect can protect specific quantum states from decoherence by using projective measurements. Here we combine the theory of weak measurements with stabilizer quantum error correction and detection…

Quantum Physics · Physics 2015-03-19 G. A. Paz-Silva , A. T. Rezakhani , J. M. Dominy , D. A. Lidar

Unsolved controversies about uncertainty relations and quantum measurements still persists nowadays. They originate around the shortcomings regarding the conventional interpretation of uncertainty relations. Here we show that the respective…

Quantum Physics · Physics 2007-05-23 S. Dumitru

In a very recent work [arXiv:2004.07451], Kim et al claimed to have made the first genuine experimental observation of the Quantum Cheshire Cat effect. We dispute this claim on the ground that the setup employed is not adequate for making…

Quantum Physics · Physics 2020-06-02 Surya Narayan Sahoo , Dipankar Home , Alex Matzkin , Urbasi Sinha

The emergence of realistic properties is a key problem in understanding the quantum-to-classical transition. In this respect, measurements represent a way to interface quantum systems with the macroscopic world: these can be driven in the…

Weak values are average quantities,therefore investigating their associated variance is crucial in understanding their place in quantum mechanics. We develop the concept of a position-postselected weak variance of momentum as cohesively as…

Quantum Physics · Physics 2015-08-10 M. R. Feyereisen

In this work we revisit the important and controversial concept of quantum weak values, aiming to provide a simplified understanding to its associated physics and the origin of anomaly. Taking the Stern-Gerlach setup as a working system, we…

Quantum Physics · Physics 2016-02-29 Lupei Qin , Wei Feng , Xin-Qi Li

A measurement consists in coupling a system to a probe and reading the output of the probe to gather information about the system. The weaker the coupling, the smaller the back-action on the system, but also the less information conveyed.…

Quantum Physics · Physics 2012-11-13 Antonio Di Lorenzo , José Carlos Egues

We prove uncertainty relations that quantitatively express the impossibility of jointly sharp preparation of pre- and post-selected quantum states for measuring incompatible observables during the weak measurement. By defining a suitable…

Quantum Physics · Physics 2014-11-27 Arun Kumar Pati , Junde Wu