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Related papers: Extremal covariant quantum operations and POVM's

200 papers

On a conformal net $\mathcal{A}$, one can consider collections of unital completely positive maps on each local algebra $\mathcal{A}(I)$, subject to natural compatibility, vacuum preserving and conformal covariance conditions. We call…

Operator Algebras · Mathematics 2023-05-23 Marcel Bischoff , Simone Del Vecchio , Luca Giorgetti

We show that the correct mathematical foundation of quantum decision theory, dealing with uncertain events, requires the use of positive operator-valued measure that is a generalization of the projection-valued measure. The latter is…

Quantum Physics · Physics 2015-03-17 V. I. Yukalov , D. Sornette

Quantum computation is the suitable orthogonal encoding of possibly holistic functional properties into state vectors, followed by a projective measurement.

Quantum Physics · Physics 2016-05-10 Karl Svozil

We show how an upper bound for the ability to discriminate any number N of candidates for the Hamiltonian governing the evolution of an open quantum system may be calculated by numerically efficient means. Our method applies an effective…

Quantum Physics · Physics 2018-05-23 Alexander Holm Kiilerich , Klaus Mølmer

Generalized measurement schemes on one part of bipartite states, which would leave the set of all separable states insensitive are explored here to understand quantumness of correlations in a more general perspecitve. This is done by…

Quantum Physics · Physics 2012-01-04 A. R. Usha Devi , A. K. Rajagopal , Sudha

In quantum theory general measurements are described by so-called Positive Operator-Valued Measures (POVMs). We show that in $d$-dimensional quantum systems an application of depolarizing noise with constant (independent of $d$) visibility…

Quantum Physics · Physics 2025-01-17 Michał Kotowski , Michał Oszmaniec

We present a parallel between commutative and non-commutative polymorphisms. Our emphasis is the applications to conditional distributions from stochastic processes. In the classical case, both the measures and the positive definite kernels…

Quantum Physics · Physics 2025-01-22 Palle E. T. Jorgensen , James Tian

The problem of how to obtain quasi-classical states for quantum groups is examined. A measure of quantum indeterminacy is proposed, which involves expectation values of some natural quantum group operators. It is shown that within any…

q-alg · Mathematics 2008-02-03 R. Delbourgo , R. B. Zhang

A quantum measurement, often referred to as positive operator-valued measurement (POVM), is a set of positive operators $P_j=P_j^\dag\geq 0$ summing to identity, $\sum_jP_j=\mathbb{1}$. This can be seen as a generalization of a probability…

Quantum Physics · Physics 2024-12-30 Albert Rico , Karol Życzkowski

The notion of perfect correlations between arbitrary observables, or more generally arbitrary POVMs, is introduced in the standard formulation of quantum mechanics, and characterized by several well-established statistical conditions. The…

Quantum Physics · Physics 2007-10-31 Masanao Ozawa

This paper is concerned with quadratic-exponential moments (QEMs) for dynamic variables of quantum stochastic systems with position-momentum type canonical commutation relations. The QEMs play an important role for statistical…

Quantum Physics · Physics 2022-11-23 Igor G. Vladimirov

Many insights into the quantum world can be found by studying it from amongst more general operational theories of physics. In this thesis, we develop an approach to the study of such theories purely in terms of the behaviour of their…

Quantum Physics · Physics 2019-02-04 Sean Tull

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

We derive an extremal equation for optimal completely-positive map which most closely approximates a given transformation between pure quantum states. Moreover, we also obtain an upper bound on the maximal mean fidelity that can be attained…

Quantum Physics · Physics 2009-11-07 Jaromir Fiurasek

In this paper we introduce a projective invarinat measure on the special unitary group. It is directly related to transition probabilities. It has some interesting connection with convex geometry. Applications to approximation of quantum…

Quantum Physics · Physics 2007-05-23 Manas Patra

Quantum estimation of the operators of a system is investigated by analyzing its Liouville space of operators. In this way it is possible to easily derive some general characterization for the sets of observables (i.e. the possible quorums)…

Quantum Physics · Physics 2009-11-06 G. M. D'Ariano , L. Maccone , M. G. A. Paris

In quantum operations, probabilities characterise both the degree of the success of a state transformation and, as density operator eigenvalues, the degree of mixedness of the final state. We give a unified treatment of pure-to-pure state…

Quantum Physics · Physics 2009-11-07 Anthony Chefles

We analyze bipartite matrices and linear maps between matrix algebras, which are respectively, invariant and covariant, under the diagonal unitary and orthogonal groups' actions. By presenting an expansive list of examples from the…

Quantum Physics · Physics 2021-08-11 Satvik Singh , Ion Nechita

Quantum Cognition has delivered a number of models for semantic memory, but to date these have tended to assume pure states and projective measurement. Here we relax these assumptions. A quantum inspired model of human word association…

Neurons and Cognition · Quantitative Biology 2018-03-29 Mojtaba Aliakbarzadeh , Kirsty Kitto

We consider a protocol to perform the optimal quantum state discrimination of $N$ linearly independent non-orthogonal pure quantum states and present a computational code. Through the extension of the original Hilbert space, it is possible…

Quantum Physics · Physics 2016-09-08 Wilson R. M. Rabelo , Alexandre G. Rodrigues , Reinaldo O. Vianna