English
Related papers

Related papers: Conditional Effects, Observables and Instruments

200 papers

We analyze the notion that physical theories are quantitative and testable by observations in experiments. This leads us to propose a new, Bayesian, interpretation of probabilities in physics that unifies their current use in classical…

Quantum Physics · Physics 2007-05-23 Francis G. Perey

Measurement models (MMs) stand at the highest structural level of quantum measurement theory. MMs can be employed to construct instruments which stand at the next level. An instrument is thought of as an apparatus that is used to measure…

Quantum Physics · Physics 2023-08-22 Stan Gudder

To begin with, it is pointed out that the form of the quantum probabil- ity formula originates in the very initial state of the object system as seen when the state is expanded with the eigen-projectors of the measured ob- servable. Making…

Quantum Physics · Physics 2016-10-23 Fedor Herbut

The presence of contextuality in quantum theory was first highlighted by Bell, Kochen and Specker, who discovered that for quantum systems of three or more dimensions, measurements cannot be viewed as revealing pre-existing properties of…

Quantum Physics · Physics 2017-04-07 Andrew W. Simmons , Joel J. Wallman , Hakop Pashayan , Stephen D. Bartlett , Terry Rudolph

Until recently, a quantum instrument was defined to be a completely positive operation-valued measure from the set of states on a Hilbert space to itself. In the last few years, this definition has been generalized to such measures between…

Quantum Physics · Physics 2023-06-08 Stanley Gudder

Within the Kolmogorov theory of probability, Bayes' rule allows one to perform statistical inference by relating conditional probabilities to unconditional probabilities. As we show here, however, there is a continuous set of alternative…

Probability · Mathematics 2014-12-05 Samuel G. Rodriques

We can learn (more) about the state a quantum system is in through measurements. We look at how to describe the uncertainty about a quantum system's state conditional on executing such measurements. We show that by exploiting the interplay…

Quantum Physics · Physics 2025-04-22 Keano De Vos , Gert de Cooman

We consider the problem of determining the state of a quantum system given one or more readings of the expectation value of an observable. The system is assumed to be a finite dimensional quantum control system for which we can influence…

Quantum Physics · Physics 2009-11-10 Domenico D'Alessandro

Quantum probabilities are defined for several important physical cases characterizing measurements with multimode quantum systems. These are the probabilities for operationally testable measurements, for operationally uncertain…

Quantum Physics · Physics 2015-06-19 V. I. Yukalov , E. P. Yukalova , D. Sornette

We study the quantum-mechanical uncertainty relation originating from the successive measurement of two observables $\hat{A}$ and $\hat{B}$, with eigenvalues $a_n$ and $b_m$, respectively, performed on the same system. We use an extension…

Quantum Physics · Physics 2020-06-02 Ady Mann , Pier A. Mello , Michael Revzen

We propose a time-of-arrival operator in quantum mechanics by conditioning on a quantum clock. This allows us to bypass some of the problems of previous proposals, and to obtain a Hermitian time of arrival operator whose probability…

Quantum Physics · Physics 2020-03-19 Lorenzo Maccone , Krzysztof Sacha

In this work a quantum analogue of Bayesian inference is considered. Based on the notion of instrument, we propose a quantum analogue of Bayes' rule, which elaborates how a prior normal state updates under observations. Besides, we…

Quantum Physics · Physics 2023-01-10 Huayu Liu

In the Contextuality-by-Default theory random variables representing measurement outcomes are labeled contextually, i.e., not only by what they measure but also under what conditions (in what contexts) the measurements are made, including…

Quantum Physics · Physics 2018-12-11 Ehtibar N. Dzhafarov

It is argued that there is a sensible way to define conditional probabilities in quantum mechanics, assuming only Bayes's theorem and standard quantum theory. These probabilities are equivalent to the ``weak measurement'' predictions due to…

Quantum Physics · Physics 2016-09-08 Aephraim M. Steinberg

After a brief introduction to Probability Bracket Notation (PBN), indicator operator and conditional density operator (CDO), we investigate probability spaces associated with various quantum systems: system with one observable (discrete or…

Probability · Mathematics 2009-11-10 Xing M. Wang

Considering a minimal number of assumptions and in the context of the timeless formalism, conditional probabilities are derived for subsequent measurements in the non-relativistic regime. Only unitary transformations are considered with…

Quantum Physics · Physics 2024-01-30 Martino Trassinelli

We state a quantum version of Bayes's rule for statistical inference and give a simple general derivation within the framework of generalized measurements. The rule can be applied to measurements on N copies of a system if the initial state…

Quantum Physics · Physics 2009-11-06 Ruediger Schack , Todd A. Brun , Carlton M. Caves

A new measure of information in quantum mechanics is proposed which takes into account that for quantum systems the only feature known before an experiment is performed are the probabilities for various events to occur. The sum of the…

Quantum Physics · Physics 2009-11-06 Caslav Brukner , Anton Zeilinger

One of the basic lessons of quantum theory is that one cannot obtain information on an unknown quantum state without disturbing it. Hence, by performing a certain measurement, we limit the other possible measurements that can be effectively…

Quantum Physics · Physics 2018-08-24 Erkka Haapasalo , Teiko Heinosaari , Takayuki Miyadera

The problem of measurement in quantum mechanics is reanalyzed within a general, strictly probabilistic framework (without reduction postulate). Based on a novel comprehensive definition of measurement the natural emergence of objective…

Quantum Physics · Physics 2007-05-23 Markus Simonius