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Related papers: Geometric characterization of mixed quantum states

200 papers

Quantum de Sitter geometry is discussed using elementary field operator algebras in Krein space quantization from an observer-independent point of view, {\it i.e.} ambient space formalism. In quantum geometry, the conformal sector of the…

General Relativity and Quantum Cosmology · Physics 2024-02-06 Mohammad Vahid Takook

The past few years have seen a revived interest in quantum geometrical characterizations of band structures due to the rapid development of topological insulators and semi-metals. Although the metric tensor has been connected to many…

Mesoscale and Nanoscale Physics · Physics 2023-03-07 Adrien Bouhon , Abigail Timmel , Robert-Jan Slager

In quantum physics, multiparticle systems are described by quantum states acting on tensor products of Hilbert spaces. This product structure leads to the distinction between product states and entangled states; moreover, one can quantify…

Quantum Physics · Physics 2026-03-06 Lisa T. Weinbrenner , Albert Rico , Kenneth Goodenough , Xiao-Dong Yu , Otfried Gühne

We consider a system with a discrete configuration space. We show that the geometrical structures associated with such a system provide the tools necessary for a reconstruction of discrete quantum mechanics once dynamics is brought into the…

Mathematical Physics · Physics 2013-12-03 Marcel Reginatto , Michael J. W. Hall

The use of geometric and symmetry techniques in quantum and classical information processing has a long tradition across the physical sciences as a means of theoretical discovery and applied problem solving. In the modern era, the emergent…

Quantum Physics · Physics 2024-09-10 Elija Perrier

Quantum computers can accurately compute ground state energies using phase estimation, but this requires a guiding state that has significant overlap with the true ground state. For large molecules and extended materials, it becomes…

Grid states form a discrete set of mixed quantum states that can be described by graphs. We characterize the entanglement properties of these states and provide methods to evaluate entanglement criteria for grid states in a graphical way.…

Quantum Physics · Physics 2018-08-28 Joshua Lockhart , Otfried Gühne , Simone Severini

We further elaborate on a phase-space picture for a system of $N$ qubits and explore the structures compatible with the notion of unbiasedness. These consist of bundles of discrete curves satisfying certain additional properties and…

Quantum Physics · Physics 2017-06-14 C. Munoz , A. B. Klimov , L. L. Sanchez-Soto

The phase space for a system of $n$ qubits is a discrete grid of $2^{n} \times 2^{n}$ points, whose axes are labeled in terms of the elements of the finite field $\Gal{2^n}$ to endow it with proper geometrical properties. We analyze the…

Quantum Physics · Physics 2012-05-10 A. B. Klimov , C. Munoz , L. L. Sanchez-Soto

We propose a detailed study of the geometric entanglement properties of pure symmetric N-qubit states, focusing more particularly on the identification of symmetric states with a high geometric entanglement and how their entanglement…

Quantum Physics · Physics 2010-07-01 J. Martin , O. Giraud , P. A. Braun , D. Braun , T. Bastin

Quantum theory of field (extended) objects without a priori space-time geometry has been represented. Intrinsic coordinates in the tangent fibre bundle over complex projective Hilbert state space $CP(N-1)$ are used instead of space-time…

General Physics · Physics 2007-05-23 Peter Leifer

Proposals for nonlinear extenstions of quantum mechanics are discussed. Two different concepts of "mixed state" for any nonlinear version of quantum theory are introduced: (i) >genuine mixture< corresponds to operational "mixing" of…

Quantum Physics · Physics 2012-12-07 Pavel Bona

When quantum mechanical qubits as elements of two dimensional complex Hilbert space are generalized to elements of even subalgebra of geometric algebra over three dimensional Euclidian space, geometrically formal complex plane becomes…

General Physics · Physics 2015-11-10 Alexander Soiguine

Quantum engineering now allows to design and construct multi-qubit states in a range of physical systems. These states are typically quite complex in nature, with disparate, but relevant properties that include both single and multi-qubit…

A unified approach to geometric, symbol and deformation quantizations on a generalized flag manifold endowed with an invariant pseudo-Kaehler structure is proposed. The Hilbert space of states is realized via the Bott-Borel-Weil theorem in…

dg-ga · Mathematics 2008-02-03 Alexander V. Karabegov

The Riemannian Bures metric on the space of (normalized) complex positive matrices is used for parameter estimation of mixed quantum states based on repeated measurements just as the Fisher information in classical statistics. It appears…

Quantum Physics · Physics 2016-09-08 J. Dittmann

The quantum state of a light beam can be represented as an infinite dimensional density matrix or equivalently as a density on the plane called the Wigner function. We describe quantum tomography as an inverse statistical problem in which…

Statistics Theory · Mathematics 2007-06-13 L. M. Artiles , R. D. Gill , M. I. Guta

Quantum state reconstruction using Neural Quantum States has been proposed as a viable tool to reduce quantum shot complexity in practical applications, and its advantage over competing techniques has been shown in numerical experiments…

Quantum Physics · Physics 2024-05-29 Haimeng Zhao , Giuseppe Carleo , Filippo Vicentini

I review recent works showing that information geometry is a useful framework to characterize quantum coherence and entanglement. Quantum systems exhibit peculiar properties which cannot be justified by classical physics, e.g. quantum…

Quantum Physics · Physics 2018-10-08 Davide Girolami

In this paper, we extend the standard formalism of quantum mechanics to a quantum theory for a total system including one internal measuring apparatus. The internality of the measuring apparatus implies that different decomposition of a…

Quantum Physics · Physics 2012-05-17 Wen-ge Wang