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In this paper, we aim to establish foundations of measurement theory in local quantum physics. For this purpose, we discuss a representation theory of completely positive (CP) instruments on arbitrary von Neumann algebras. We introduce a…

Mathematical Physics · Physics 2015-11-20 Kazuya Okamura , Masanao Ozawa

We consider the problem of determining the mixed quantum state of a large but finite number of identically prepared quantum systems from data obtained in a sequence of ideal (von Neumann) measurements, each performed on an individual copy…

Quantum Physics · Physics 2009-11-10 Franz Embacher , Heide Narnhofer

We show that the key problems of quantum measurement theory, namely the reduction of the wave packet of a microsystem and the specification of its quantum state by a macroscopic measuring instrument, may be rigorously resolved within the…

Mathematical Physics · Physics 2009-11-11 Geoffrey Sewell

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 analyse non ideal quantum measurements described as scattering processes providing an estimator of the measured quantity. The sensitivity is expressed as an equivalent input noise. We address the Von Neumann problem of chained…

Quantum Physics · Physics 2007-05-23 Jean-Michel Courty , Francesca Grassia , Serge Reynaud

Entanglement is a special feature of the quantum world that reflects the existence of subtle, often non-local, correlations between local degrees of freedom. In topological theories such non-local correlations can be given a very intuitive…

High Energy Physics - Theory · Physics 2020-01-31 D. Melnikov , A. Mironov , S. Mironov , A. Morozov , An. Morozov

The pure state space of Quantum Mechanics is investigated as Hermitian Symmetric Kaehler manifold. The classical principles of Quantum Mechanics (Quantum Superposition Principle, Heisenberg Uncertainty Principle, Quantum Probability…

Quantum Physics · Physics 2009-11-07 R. Cirelli , M. Gatti , A. Maniá

Quantum coherence is a fundamental feature of quantum physics and plays a significant role in quantum information processing. By generalizing the resource theory of coherence from von Neumann measurements to positive operator-valued…

Quantum Physics · Physics 2023-05-12 Meng-Li Guo , Jin-Min Liang , Bo Li , Shao-Ming Fei , Zhi-Xi Wang

Experimental characterizations of a quantum system involve the measurement of expectation values of observables for a preparable state |psi> of the quantum system. Such expectation values can be measured by repeatedly preparing |psi> and…

Quantum Physics · Physics 2009-11-13 Emanuel Knill , Gerardo Ortiz , Rolando D. Somma

In this paper, we construct a sheaf-based topos quantum theory. It is well known that a topos quantum theory can be constructed on the topos of presheaves on the category of commutative von Neumann algebras of bounded operators on a Hilbert…

Mathematical Physics · Physics 2015-06-19 Kunji Nakayama

We consider the problem of designing a measurement to minimize the probability of a detection error when distinguishing between a collection of possibly non-orthogonal mixed quantum states. We show that if the quantum state ensemble…

Quantum Physics · Physics 2009-11-10 Yonina C. Eldar

Estimating properties of a quantum state is an indispensable task in various applications of quantum information processing. To predict properties in the post-processing stage, it is inherent to first perceive the quantum state with a…

Quantum Physics · Physics 2024-02-29 Yinfei Li , Sanjib Ghosh , Jiangwei Shang , Qihua Xiong , Xiangdong Zhang

Characterization of quantum systems from experimental data is a central problem in quantum science and technology. But which measurements should be used to gather data in the first place? While optimal measurement choices can be worked out…

Quantum Physics · Physics 2025-07-15 Jiaxin Huang , Yan Zhu , Giulio Chiribella , Ya-Dong Wu

The space of quantum states can be endowed with a metric structure using the second order derivatives of the relative entropy, giving rise to the so-called Kubo-Mori-Bogoliubov inner product. We explore its geometric properties on the…

Quantum Physics · Physics 2024-07-23 Harry J. D. Miller

In this paper, we deal with quantum theories on presheaves and sheaves on context categories consisting of commutative von Neumann algebras of bounded operators on a Hilbert space, from two viewpoints. One is to reduce presheaf-based topos…

Mathematical Physics · Physics 2017-01-04 Kunji Nakayama

Measurement quantum mechanics, the theory of a quantum system which undergoes a measurement process, is introduced by a loop of mathematical equivalencies connecting previously proposed approaches. The unique phenomenological parameter of…

Condensed Matter · Physics 2009-10-28 Carlo Presilla , Roberto Onofrio , Ubaldo Tambini

Starting from a new principle inspired by quantum tomography rather than from Born's rule, this paper gives a self-contained deductive approach to quantum mechanics and quantum measurement. A suggestive notion for what constitutes a quantum…

Quantum Physics · Physics 2024-05-22 Arnold Neumaier

State transformations in quantum mechanics are described by completely positive maps which are constructed from quantum channels. We call a finest sharp quantum channel a context. The result of a measurement depends on the context under…

Quantum Physics · Physics 2022-09-01 Stan Gudder

In the Bayesian approach to quantum mechanics, probabilities--and thus quantum states--represent an agent's degrees of belief, rather than corresponding to objective properties of physical systems. In this paper we investigate the concept…

Quantum Physics · Physics 2007-05-23 Carlton M. Caves , Christopher A. Fuchs , Ruediger Schack

In Quantum Physics, a measurement is represented by a projection on some closed subspace of a Hilbert space. We study algebras of operators that abstract from the algebra of projections on closed subspaces of a Hilbert space. The properties…

Quantum Physics · Physics 2007-05-23 Daniel Lehmann , Kurt Engesser , Dov M. Gabbay