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Related papers: Are the 'weak measurements' really measurements?

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Measurement plays a quintessential role in the control of quantum systems. Beyond initialization and readout which pertain to projective measurements, weak measurements in particular, through their back-action on the system, may enable…

Quantum Physics · Physics 2022-06-07 Yunzhao Wang , Kyrylo Snizhko , Alessandro Romito , Yuval Gefen , Kater Murch

The average result of a weak measurement of some observable $A$ can, under post-selection of the measured quantum system, exceed the largest eigenvalue of $A$. The nature of weak measurements, as well as the presence of post-selection and…

Quantum Physics · Physics 2014-11-13 Matthew F. Pusey

Quantum measurements can be generalized to include complex quantities. It is possible to relate the quantum weak values of projection operators to the third order Bargmann invariants. The argument of the weak value becomes, up to a sign,…

Quantum Physics · Physics 2021-09-22 Z. Gedik

The products of weak values of quantum observables are shown to be of value in deriving quantum uncertainty and complementarity relations, for both weak and strong measurement statistics. First, a 'product representation formula' allows the…

Quantum Physics · Physics 2016-06-08 Michael J. W. Hall , Arun Kumar Pati , Junde Wu

To-date, the most elaborated attempt to complete quantum mechanics by the addition of hidden variables is the de Broglie-Bohm (pilot wave) theory (dBBT). It endows particles with definite positions at all times. Their evolution is governed…

Quantum Physics · Physics 2025-03-12 Johannes Fankhauser , Patrick M. Dürr

We review the definition and the concepts of the weak values and some measurement model to extract the weak value. This material is based on the author Ph.D. thesis "Time in Weak Values and Discrete Time Quantum Walk" at Tokyo Institute of…

Quantum Physics · Physics 2021-07-19 Yutaka Shikano

Necessary and sufficient conditions for weak and vague convergence of measures are important for a diverse host of applications. This paper aims to give a comprehensive description of the relationship between the two modes of convergence…

Functional Analysis · Mathematics 2022-08-04 Martin Herdegen , Gechun Liang , Osian Shelley

Measurement uncertainty and experimental error are important concepts taught in undergraduate physics laboratories. Although student ideas about error and uncertainty in introductory classical mechanics lab experiments have been studied…

Physics Education · Physics 2021-09-20 Emily M. Stump , Courtney L. White , Gina Passante , N. G. Holmes

Quantum physics constrains the accuracy of joint measurements of incompatible observables. Here we test tight measurement-uncertainty relations using single photons. We implement two independent, idealized uncertainty-estimation methods,…

Recently proposed idea of "protective" measurement of a quantum state is critically examined, and generalized. Earlier criticisms of the idea are discussed and their relevance to the proposal assessed. Several constraints on measuring…

Quantum Physics · Physics 2011-08-24 N. D. Hari Dass , Tabish Qureshi

Basic quantum information measures involved in the information analysis of quantum systems are considered. It is shown that the main quantum information measurement methods depend on whether the corresponding quantum events are compatible…

Quantum Physics · Physics 2007-05-23 B. A. Grishanin , V. N. Zadkov

The apparent random outcome of a quantum measurement is conjectured to be fundamentally determined by the microscopic state of the macroscopic measurement apparatus. The apparatus state thus plays the role of a hidden variable which, in…

Quantum Physics · Physics 2017-03-22 Jean-Marc Sparenberg , Réda Nour , Aylin Manço

We explore the possibility of using "weak measurements" without "weak value" for quantum state estimation. Since for weak measurements the disturbance caused during each measurement is small, we can rescue the state, unlike for the case of…

Quantum Physics · Physics 2019-07-23 Debmalya Das , Arvind

Weak measurements are a new tool for characterizing post-selected quantum systems during their evolution. Weak measurement was originally formulated in terms of von Neumann interactions which are practically available for only the simplest…

Quantum Physics · Physics 2009-11-11 J. S. Lundeen , K. J. Resch

A model is proposed for the statistical analysis of arbitrary-strength quantum measurements, based on a picture of "sampling weak values" from different configurations of the system. The model is comprised of two elements: a "local weak…

Quantum Physics · Physics 2007-05-23 Alonso Botero

Weak value measurements have recently given rise to a large interest for both the possibility of measurement amplification and the chance of further quantum mechanics foundations investigation. In particular, a question emerged about weak…

The impossibility of measuring noncommuting quantum mechanical observables is one of the most fascinating consequences of the quantum mechanical postulates. Hence, to date the investigation of quantum measurement and projection is a…

Mesoscale and Nanoscale Physics · Physics 2010-09-06 Adam Bednorz , Wolfgang Belzig

Since its introduction 25 years ago, the quantum weak value has gradually transitioned from a theoretical curiosity to a practical laboratory tool. While its utility is apparent in the recent explosion of weak value experiments, its…

Quantum Physics · Physics 2014-04-02 Justin Dressel , Mehul Malik , Filippo M. Miatto , Andrew N. Jordan , Robert W. Boyd

The measurement problem is seen as an ambiguity of quantum mechanics, or, beyond that, as a contradiction within the theory: Quantum mechanics offers two conflicting descriptions of the Wigner's-friend experiment. As we argue in this note…

Quantum Physics · Physics 2019-12-09 Arne Hansen , Stefan Wolf

In combination with post-selection, weak measurements can lead to surprising results known as anomalous weak values. These lie outside the bounds of the spectrum of the relevant observable, as in the canonical example of measuring the spin…

Quantum Physics · Physics 2022-01-27 Asger C. Ipsen