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Related papers: Half a state, half an operator: a general formulat…

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Quantum steering refers to the non-classical correlations that can be observed between the outcomes of measurements applied on half of an entangled state and the resulting post-measured states that are left with the other party. From an…

Quantum Physics · Physics 2017-01-06 D. Cavalcanti , P. Skrzypczyk

In this paper, we introduce and study frame of operators in quaternionic Hilbert spaces as a generalization of g frames which in turn generalized various notions like Pseduo frames, bounded quasi-projectors and frame of subspaces (fusion…

Functional Analysis · Mathematics 2020-03-03 S. K. Sharma , A. M. Jarrah , S. K. Kaushik

For a bi-partite quantum system defined in a finite dimensional Hilbert space we investigate in what sense entanglement change and interactions imply each other. For this purpose we introduce an entanglement operator, which is then shown to…

Quantum Physics · Physics 2009-11-07 J. Gemmer , G. Mahler

The stabiliser formalism allows the efficient description of a sizeable class of pure as well as mixed quantum states of N-qubit systems. That same formalism has important applications in the field of quantum error correcting codes, where…

Quantum Physics · Physics 2009-11-11 Koenraad M. R. Audenaert , Martin B. Plenio

Different versions of the notion of a state have been formulated for various so-called quantum structures. In this paper, we investigate the interplay among states on synaptic algebras and on its sub-structures. A synaptic algebra is a…

Mathematical Physics · Physics 2017-04-05 David J. Foulis , Anna Jencova , Sylvia Pulmannova

In this paper, we investigate a rather general system of two operator equations that has the structure of a viscous or nonviscous Cahn--Hilliard system in which nonlinearities of double-well type occur. Standard cases like regular or…

Analysis of PDEs · Mathematics 2019-08-05 Pierluigi Colli , Gianni Gilardi , Jürgen Sprekels

We propose a non-commutative extension of the Pauli stabilizer formalism. The aim is to describe a class of many-body quantum states which is richer than the standard Pauli stabilizer states. In our framework, stabilizer operators are…

Quantum Physics · Physics 2015-06-11 Xiaotong Ni , Oliver Buerschaper , Maarten Van den Nest

Manipulation of superpositions of discrete quantum states has a mathematical counterpart in the motion of a unit-length statevector in an N-dimensional Hilbert space. Any such statevector motion can be regarded as a succession of…

Quantum Physics · Physics 2008-03-04 E. S. Kyoseva , N. V. Vitanov , B. W. Shore

Quantum operations (QO) describe any state change allowed in quantum mechanics, such as the evolution of an open system or the state change due to a measurement. We address the problem of which unitary transformations and which observables…

Quantum Physics · Physics 2009-11-10 F. Buscemi , G. M. D'Ariano , M. F. Sacchi

In this paper we study shorted operators relative to two different subspaces, for bounded operators on infinite dimensional Hilbert spaces. We define two notions of complementability in the sense of Ando for operators, and study the…

Functional Analysis · Mathematics 2007-05-23 Jorge Antezana , Gustavo Corach , Demetrio Stojanoff

Proper splittings of operators are commonly used to study the convergence of iterative processes. In order to approximate solutions of operator equations, in this article we deal with proper splittings of closed range bounded linear…

Functional Analysis · Mathematics 2024-03-18 Guillermina Fongi , María Celeste Gonzalez

The construction of a class of unitary operators generating linear superpositions of generalized coherent states from the ground state of a quantum harmonic oscillator is reported. Such a construction, based on the properties of a new ad…

Quantum Physics · Physics 2013-06-13 Antonino Messina , Gheorghe Draganescu

A notion of super operator system is defined which generalizes the usual notion of operator systems to include certain unital involutive operator spaces which cannot be represented completely isometric as a concrete operator system on some…

Operator Algebras · Mathematics 2013-08-05 Ulrich Haag

For states in infinite dimensional Hilbert spaces entanglement quantities like the entanglement of distillation can become infinite. This leads naturally to the question, whether one system in such an infinitely entangled state can serve as…

Quantum Physics · Physics 2007-05-23 M. Keyl , D. Schlingemann , R. F. Werner

Recently, we have shown how the interpretation of quantum mechanics due to Lande' can be used to derive from first principles generalized formulas for the operators and some eigenvectors for spin 1/2 Though we gave the operators for all the…

Quantum Physics · Physics 2007-05-23 Habatwa Vincent Mweene

Phase operators are constructed using a Klauder-Berezin coherent state quantization in finite Hilbert subspaces of the Hilbert space of Fourier series. The study of infinite dimensional limits of mean values of some observables phase leads…

Quantum Physics · Physics 2016-08-16 Pedro L. García de León , Jean-Pierre Gazeau

The moment operators of a semispectral measure having the structure of the convolution of a positive measure and a semispectral measure are studied, with paying attention to the natural domains of these unbounded operators. The results are…

Quantum Physics · Physics 2009-11-13 Jukka Kiukas , Pekka Lahti , Kari Ylinen

Bifractional displacement operators, are introduced by performing two fractional Fourier transforms on displacement operators. They are shown to be special cases of elements of the group G, that contains both displacements and squeezing…

Quantum Physics · Physics 2015-08-14 S. Agyo , C. Lei , A. Vourdas

We propose in this work a concept of integrability for quantum systems, which corresponds to the concept of noncommutative integrability for systems in classical mechanics. We determine a condition for quantum operators which can be a…

Mathematical Physics · Physics 2010-01-27 M. Marino , N. N. Nekhoroshev

The purpose of the article is to generalize the concept of approximate Birkhoff-James orthogonality, in the semi-Hilbertian structure. Given a positive operator $ A $ on a Hilbert space $ \mathbb{H}, $ we define $ (\epsilon,A)- $approximate…

Functional Analysis · Mathematics 2024-08-14 Jeet Sen , Debmalya Sain , Kallol Paul