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Related papers: A Result About the Classification of Quantum Covar…

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In this work, we construct different classes of coherent states related to a quantum system, recently studied in [1], of an electron moving in a plane in uniform external magnetic and electric fields which possesses both discrete and…

Quantum Physics · Physics 2021-12-22 Isiaka Aremua , Laure Gouba

This paper is concerned with the generation of Gaussian invariant states in cascades of open quantum harmonic oscillators governed by linear quantum stochastic differential equations. We carry out infinitesimal perturbation analysis of the…

Optimization and Control · Mathematics 2017-06-15 Igor G. Vladimirov , Ian R. Petersen , Matthew R. James

We introduce a random matrix model for the stationary covariance of multivariate Ornstein-Uhlenbeck processes with heterogeneous temperatures, where the covariance is constrained by the Sylvester-Lyapunov equation. Using the replica method,…

Disordered Systems and Neural Networks · Physics 2025-01-30 Leonardo Ferreira , Fernando Metz , Paolo Barucca

We show that higher order inter-group covariances involving even number of qubits are necessarily positive semidefinite for N qubit separable states, which are completely symmetric under permutations of the qubits. This identification leads…

Quantum Physics · Physics 2009-11-13 A. R. Usha Devi , R. Prabhu , A. K. Rajagopal

We present a general framework and procedure to derive uncertainty relations for observables of quantum systems in a covariant manner. All such relations are consequences of the positive semidefiniteness of the density matrix of a general…

Quantum Physics · Physics 2012-05-24 J Solomon Ivan , Krishna Kumar Sabapathy , N. Mukunda , R. Simon

A quantum state for being an eigenstate of some local Hamiltonian should be constraint by zero energy variance and consequently, the constraint is rather strong that a single eigenstate may uniquely determine the Hamiltonian. For…

Quantum Physics · Physics 2024-12-17 Xu-Dan Xie , Zheng-Yuan Xue , Dan-Bo Zhang

In multimode optical systems, the spectral covariance matrix encodes all the information about quantum correlations between the quadratures of Gaussian states. Recent research has revealed that, in scenarios that are more common than…

Quantum Physics · Physics 2026-03-11 Bakhao Dioum , Virginia D'Auria , Giuseppe Patera

Uncertainty relations are usually stated as bounds on selected combinations of variances, but the full covariance matrix contains substantially richer information about the geometry of quantum state space and about the operational…

Quantum Physics · Physics 2026-05-13 Dimpi Thakuria , Shuheng Liu , Giuseppe Vitagliano , Konrad Szymański

We consider (self-adjoint) families of infinite matrices of noncommutative random variables such that the joint distribution of their entries is invariant under conjugation by a free quantum group. For the free orthogonal and…

Operator Algebras · Mathematics 2011-01-05 Stephen Curran , Roland Speicher

Quantum inverse problem is defined as how to determine a local Hamiltonian from a single eigenstate? This question is valid not only in Hermitian system but also in non-Hermitian system. So far, most attempts are limited to Hermitian…

Quantum Physics · Physics 2024-03-01 Yin Tang , W. Zhu

Eigenvalues of a density matrix characterize well the quantum state's properties, such as coherence and entanglement. We propose a simple method to determine all the eigenvalues of an unknown density matrix of a finite-dimensional system in…

Quantum Physics · Physics 2014-01-24 Tohru Tanaka , Yukihiro Ota , Mitsunori Kanazawa , Gen Kimura , Hiromichi Nakazato , Franco Nori

Permutation symmetries of multipartite quantum states are defined only when the constituent subsystems are of equal dimensions. In this work we extend this notion of permutation symmetry to heterogeneous systems, that is, systems composed…

Quantum Physics · Physics 2017-06-02 Gururaj Kadiri , S Sivakumar

Gaussian states are the backbone of quantum information protocols with continuous variable systems, whose power relies fundamentally on the entanglement between the different modes. In the case of global pure states, knowledge of the…

Quantum Physics · Physics 2017-11-08 Fernando Nicacio , Andrea Valdés-Hernández , Ana P. Majtey , Fabricio Toscano

Based on empirical evidence, quantum systems appear to be strictly linear and gauge invariant. This work uses concise mathematics to show that quantum eigenvalue equations on a one dimensional ring can either be gauge invariant or have a…

Quantum Physics · Physics 2014-07-15 Arthur Davidson

Variational algorithms for strongly correlated chemical and materials systems are one of the most promising applications of near-term quantum computers. We present an extension to the variational quantum eigensolver that approximates the…

Quantum Physics · Physics 2020-08-26 William J. Huggins , Joonho Lee , Unpil Baek , Bryan O'Gorman , K. Birgitta Whaley

In this work, we study the circuit complexity for generalized coherent states in thermal systems by adopting the covariance matrix approach. We focus on the coherent thermal (CT) state, which is non-Gaussian and has a nonvanishing one-point…

High Energy Physics - Theory · Physics 2020-07-01 Minyong Guo , Zhong-Ying Fan , Jie Jiang , Xiangjing Liu , Bin Chen

The symmetry study of main differential equations of mechanics and electrodynamics has shown, that differential equations, which are invariant under transformations of groups, which are symmetry groups of mathematical numbers (considered…

Mathematical Physics · Physics 2015-06-15 Dmitri Yerchuck , Alla Dovlatova , Andrey Alexandrov

Estimating the eigenvalues of non-normal matrices is a foundational problem with far-reaching implications, from modeling non-Hermitian quantum systems to analyzing complex fluid dynamics. Yet, this task remains beyond the reach of standard…

Quantum Physics · Physics 2025-10-23 Yukun Zhang , Yusen Wu , Xiao Yuan

We address quantum systems isospectral to the harmonic oscillator, as those found within the framework of supersymmetric quantum mechanics, as potential resources for continuous variable quantum information. These deformed oscillator…

Quantum Physics · Physics 2025-04-04 Abdelatif Chabane , Sidali Mohammdi , Abdelhakim Gharbi , Matteo G. A. Paris

In the context of a two-parameter $(\alpha, \beta)$ deformation of the canonical commutation relation leading to nonzero minimal uncertainties in both position and momentum, the harmonic oscillator spectrum and eigenvectors are determined…

Mathematical Physics · Physics 2008-11-26 C. Quesne , V. M. Tkachuk
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