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Related papers: Orthogonality relations in Quantum Tomography

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We show how quantum mechanics can be understood as a space-time theory provided that its spatial continuum is modelled by a variable real number (qrumber) continuum. Such a continuum can be constructed using only standard Hilbert space…

Quantum Physics · Physics 2007-05-23 J. Corbett , T. Durt

We introduce a procedure based on quantum expectation values of measurement observables to characterize quantum coherence. Our measure allows one to quantify coherence without having to perform tomography of the quantum state, and can be…

On the base of symplectic quantum tomogram we define a probability distribution on the plane. The dual map transfers all observables which are polynomials of the position and momentum operators to the set of polynomials of two variables. In…

Quantum Physics · Physics 2015-03-17 Grigori G. Amosov , Andrey I. Dnestryan

We propose a tomographic approach to study quantum nonlocality in continuous variable quantum systems. On one hand we derive a Bell-like inequality for measured tomograms. On the other hand, we introduce pseudospin operators whose…

Quantum Physics · Physics 2009-11-10 Stefano Mancini , Vladimir I. Man'ko , Evgeny V. Shchukin , Paolo Tombesi

We show that quantum theory (QT) is a substructure of classical probabilistic physics. The central quantity of the classical theory is Hamilton's function, which determines canonical equations, a corresponding flow, and a Liouville equation…

Quantum Physics · Physics 2020-04-06 Ulf Klein

We study the mirror-field interaction in several frameworks: when it is driven, when it is affected by an environment and when a two-level atom is introduced in the cavity. By using operator techniques we show how these problems may be…

Quantum Physics · Physics 2015-06-02 C. Ventura-Velázquez , B. M. Rodríguez-Lara , H. M. Moya-Cessa

Identifying the Hamiltonian of a quantum system from experimental data is considered. General limits on the identifiability of model parameters with limited experimental resources are investigated, and a specific Bayesian estimation…

Quantum Physics · Physics 2019-10-15 S. G. Schirmer , F. C. Langbein

Geometric quantum mechanics aims to express the physical properties of quantum systems in terms of geometrical features preferentially selected in the space of pure states. Geometric characterisations are given here for systems of one, two,…

Quantum Physics · Physics 2007-06-13 Dorje C. Brody , Anna C. T. Gustavsson , Lane P. Hughston

We define a formal framework for reasoning about linear-time properties of quantum systems in which quantum automata are employed in the modeling of systems and certain closed subspaces of state (Hilbert) spaces are used as the atomic…

Quantum Physics · Physics 2011-01-04 Mingsheng Ying , Yangjia Li , Nengkun Yu , Yuan Feng

Bohmian mechnaics is the most naively obvious embedding imaginable of Schr\"odingers's equation into a completely coherent physical theory. It describes a world in which particles move in a highly non-Newtonian sort of way, one which may at…

Quantum Physics · Physics 2016-08-16 Detlef Dürr , Sheldon Goldstein , Nino Zangh\`ı

Randomized measurements are useful for analyzing quantum systems especially when quantum control is not fully perfect. However, their practical realization typically requires multiple rotations in the complex space due to the adoption of…

Quantum Physics · Physics 2025-08-28 Jin-Min Liang , Satoya Imai , Shuheng Liu , Shao-Ming Fei , Otfried Gühne , Qiongyi He

The development of estimation and control theories for quantum systems is a fundamental task for practical quantum technology. This vision article presents a brief introduction to challenging problems and potential opportunities in the…

Quantum Physics · Physics 2022-01-19 Daoyi Dong , Ian R Petersen

Schwinger's quantization scheme is extended in order to solve the problem of the formulation of quantum mechanics on a space with a group structure. The importance of Killing vectors in a quantization scheme is showed. Usage of these…

High Energy Physics - Theory · Physics 2011-09-13 N. Chepilko , A. Romanenko

The experimental evaluation of many quantum mechanical quantities requires the estimation of several directly measurable observables, such as local observables. Due to the necessity to repeat experiments on individual quantum systems in…

Quantum Physics · Physics 2024-06-10 Ruidi Zhu , Ciara Pike-Burke , Florian Mintert

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

In this report we present a general approach for estimating quantum circuits by means of measurements. We apply the developed general approach for estimating the quality of superconducting and optical quantum chips. Using the methods of…

Quantum Physics · Physics 2019-06-18 Yu. I. Bogdanov , N. A. Bogdanova , B. I. Bantysh , D. V. Fastovets , V. F. Lukichev

The canonical Schmidt decomposition of quantum states is discussed and its implementation to the Quantum Computation Simulator is outlined. In particular, the semiorder relation in the space of quantum states induced by the lexicographic…

Quantum Physics · Physics 2009-03-12 Roman Gielerak , Marek Sawerwain

Characterizing entanglement is central for quantum information science. Special observables which indicate entanglement, so-called entanglement witnesses, are a widely used tool for this task. The construction of these witnesses typically…

Quantum Physics · Physics 2024-09-30 Chengjie Zhang , Sophia Denker , Ali Asadian , Otfried Gühne

Quantum systems with real energies generated by an apparently non-Hermitian Hamiltonian may re-acquire the consistent probabilistic interpretation via an ad hoc metric which specifies the set of observables in the updated Hilbert space of…

Quantum Physics · Physics 2008-05-14 Miloslav Znojil

We present a quantum algorithm that additively approximates the value of a tensor network to a certain scale. When combined with existing results, this provides a complete problem for quantum computation. The result is a simple new way of…

Quantum Physics · Physics 2010-02-09 Itai Arad , Zeph Landau