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Related papers: Nonclassicality in Weak Measurements

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Quantum weak measurement, measuring some observable quantities within the selected subensemble of the entire quantum ensemble, can produce many interesting results such as the superluminal phenomena. An outcome of such a measurement is the…

Quantum Physics · Physics 2017-01-24 Miao Zhang

An analysis of errors in measurement yields new insight into the penetration of quantum particles into classically forbidden regions. In addition to ``physical" values, realistic measurements yield ``unphysical" values which, we show, can…

High Energy Physics - Theory · Physics 2009-10-22 Y. Aharonov , S. Popescu , D. Rohrlich , L. Vaidman

Weak measurements with imaginary weak values are reexamined in light of recent experimental results. The shift of the meter, due to the imaginary part of the weak value, is derived via the probability of postselection, which allows…

Quantum Physics · Physics 2014-07-16 Yaron Kedem

A precise definition of "weak [quantum] measurements" and "weak value" (of a quantum observable) is offered, and simple finite dimensional examples are given showing that weak values are not unique and therefore probably do not correspond…

Quantum Physics · Physics 2009-10-01 Stephen Parrott

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

When the weak value of a projector is 1, a quantum system behaves as in that eigenstate with probability 1. By definition, however, the weak value may take an anomalous value lying outside the range of probability like -1. From the…

Quantum Physics · Physics 2016-12-21 Kazuhiro Yokota , Nobuyuki Imoto

In the weak measurement formalism of Y. Aharonov et al. the so-called weak value A_w of any observable A is generally a complex number. We derive a physical interpretation of its value in terms of the shift in the measurement pointer's mean…

Quantum Physics · Physics 2009-11-13 Richard Jozsa

Is it possible that a measurement of a spin component of a spin-1/2 particle yields the value 100? In 1988 Aharonov, Albert and Vaidman argued that upon pre- and postselection of particular spin states, weakening the coupling of a standard…

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

A relation is obtained between weak values of quantum observables and the consistency criterion for histories of quantum events. It is shown that ``strange'' weak values for projection operators (such as values less than zero) always…

Quantum Physics · Physics 2007-05-23 R. E. Kastner

This work will incorporate a few related tools for addressing the conceptual difficulties arising from sewing together classical and quantum mechanics: deterministic operators, weak measurements and post-selection. Weak Measurement, based…

Quantum Physics · Physics 2016-12-21 Eliahu Cohen , Yakir Aharonov

The exact conditions on valid pointer states for weak measurements are derived. It is demonstrated that weak measurements can be performed with any pointer state with vanishing probability current density. This condition is found both for…

Quantum Physics · Physics 2009-11-10 Lars M. Johansen

Weak measurements have an increasing number of applications in contemporary quantum mechanics. They were originally described as a weak interaction that slightly entangled the translational degrees of freedom of a particle to its spin,…

Weak values are quantities accessed through quantum experiments involving weak measurements and post-selection. It has been shown that 'anomalous' weak values (those lying beyond the eigenvalue range of the corresponding operator) defy…

Quantum Physics · Physics 2019-10-23 Ravi Kunjwal , Matteo Lostaglio , Matthew F. Pusey

A weak measurement performed on a pre- and post-selected quantum system can result in an average value that lies outside of the observable's spectrum. This effect, usually referred to as an "anomalous weak value", is generally believed to…

Quantum Physics · Physics 2019-10-16 Alastair A. Abbott , Ralph Silva , Julian Wechs , Nicolas Brunner , Cyril Branciard

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 arrival time probability distribution is defined by analogy with the classical mechanics. The difficulty of requirement to have the values of non-commuting operators is circumvented using the concept of weak measurements. The proposed…

Quantum Physics · Physics 2009-11-10 J. Ruseckas , B. Kaulakys

The presence of negative values in the Wigner quasiprobability distribution is deemed one of the hallmarks of nonclassical phenomena in quantum systems. Here we demonstrate a classical model of squeezed light that, when combined with…

Quantum Physics · Physics 2026-01-27 Brian R. La Cour

"Weak measurements" -- involving a weak unitary interaction between a quantum system and a meter followed by a projective measurement -- are investigated when the system has a non-Hermitian Hamiltonian. We show in particular how the…

Quantum Physics · Physics 2012-12-21 A. Matzkin

Weak measurement is an important technique for detecting the tiny spin-dependent splitting in photonic spin Hall effect. The weak measurement is only valid when the probe wavefunction remains almost undisturbed during the procedure of…

Optics · Physics 2015-05-19 Shizhen Chen , Xinxing Zhou , Chengquan Mi , Hailu Luo , Shuangchun Wen