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Related papers: Quantum Averages of Weak Values

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Measurement in quantum mechanics is generally described as an irreversible process that perturbs the wavefunction describing a quantum system. In this work we establish a formal connection between the measurement description within the…

Quantum Physics · Physics 2016-05-17 Fabio L. Traversa , Guillermo Albareda

Svensson [Found. Phys. 45, 1645 (2015)] argued that the concept of the weak value of an observable of a pre- and post-selected quantum system cannot be applied when the expectation value of the observable in the initial state vanishes.…

Quantum Physics · Physics 2022-10-12 Alon Ben Israel , L. Vaidman

In the paper "Does the weak trace show the past of a quantum particle?" [arXiv:2109.14060v2], it is argued that null weak values of the spatial projectors are inadequate to infer the presence of a quantum particle at an intermediate time…

Quantum Physics · Physics 2022-02-24 Q. Duprey , A. Matzkin

Based on a recent relational formulation of quantum reference frame transformations, especially with a case of quantum spatial translations in particular, we analyzed how the `value' of an observable for a fixed state change. That is the…

Quantum Physics · Physics 2021-12-09 Otto C. W. Kong

An analysis of errors in measurement yields new insight into classically forbidden quantum processes. In addition to "physical" values, a realistic measurement can yield "unphysical" values; we show that in {\it sequences} of measurements,…

Condensed Matter · Physics 2009-10-22 Daniel Rohrlich , Yakir Aharonov , Sandu Popescu , Lev Vaidman

In this chapter we offer an introduction to weak values from a three-fold perspective: first, outlining the protocols that enable their experimental determination; next, deriving their correlates in the quantum formalism and, finally,…

Quantum Physics · Physics 2026-02-04 Xabier Oianguren-Asua , Albert Solé , Carlos F. Destefani , Xavier Oriols

While ultimately they are described by quantum mechanics, macroscopic mechanical systems are nevertheless observed to follow the trajectories predicted by classical mechanics. Hence, in the regime defining macroscopic physics, the…

Quantum Physics · Physics 2007-05-23 Tanmoy Bhattacharya , Salman Habib , Kurt Jacobs

Recently a study of the first superposed mechanical quantum object ("machine") visible to the naked eye was published. However, as we show, it turns out that if the object would actually be observed, i.e. would interact with an optical…

General Physics · Physics 2015-04-01 Johan Hansson

Weak values, obtained from weak measurements, attempt to describe the properties of a quantum system as it evolves from an initial to a final state, without practically altering this evolution. Trajectories can be defined from weak…

Quantum Physics · Physics 2015-07-09 Alex Matzkin

We propose a system of equations to describe the interaction of a quasiclassical variable $X$ with a set of quantum variables $x$ that goes beyond the usual mean field approximation. The idea is to regard the quantum system as continuously…

Quantum Physics · Physics 2009-10-30 L. Diosi , J. J. Halliwell

Weak measurements offer new insights into the behavior of quantum systems. Combined with post-selection, quantum mechanics predicts a range of new experimentally testable phenomena. In this paper I consider weak measurements performed on…

Quantum Physics · Physics 2009-11-13 P. C. W. Davies

A weak measurement consists in coupling a system to a probe in such a way that constructive interference generates a large output. So far, only the average output of the probe and its variance were studied. Here, the characteristic function…

Quantum Physics · Physics 2012-03-07 Antonio Di Lorenzo

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

Using the quantum transition path time probability distribution we show that time averaging of weak values leads to unexpected results. We prove a weak value time energy uncertainty principle and time energy commutation relation. We also…

Quantum Physics · Physics 2018-09-05 Eli Pollak , S. Miret-Artés

Every measurement determines a single value as its outcome, and yet quantum mechanics predicts it only probabilistically. The Kochen-Specker theorem and Bell's inequality are often considered to reject a realist view but favor a skeptical…

General Physics · Physics 2025-10-30 Masanao Ozawa

The role of the equivalence principle in the context of non-relativistic quantum mechanics and matter wave interferometry, especially atom beam interferometry, will be discussed. A generalised form of the weak equivalence principle which is…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Claus Lämmerzahl

The "anomalous" values of C. Ferrie and J. Combes in Phys. Rev. Lett. 113, 120404 (2014) say nothing about quantum - or even classical - physics. They are not analogues of the weak values that emerge when we describe the quantum world via…

Quantum Physics · Physics 2014-10-03 Yakir Aharonov , Daniel Rohrlich

We have previously presented a version of the Weak Equivalence Principle for a quantum particle as an exact analog of the classical case, based on the Heisenberg picture analysis of free particle motion. Here, we take that to a full…

General Relativity and Quantum Cosmology · Physics 2025-06-17 Otto C. W. Kong

It is proposed a possible new approach of quantum measurements (QMS), disconnected of the traditional interpretation of uncertainty relations and independent of any appeal to the strange idea of collapse (reduction) of wave functions. The…

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

The weak value of an observable is experimentally accessible by weak measurements as theoretically analyzed by Aharonov et al. and recently experimentally demonstrated. We introduce a weak operator associated with the weak values and give a…

Quantum Physics · Physics 2010-06-11 Yutaka Shikano , Akio Hosoya