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Related papers: Geometric characterization of mixed quantum states

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The geometric formulation of quantum mechanics is a very interesting field of research which has many applications in the emerging field of quantum computation and quantum information, such as schemes for optimal quantum computers. In this…

Quantum Physics · Physics 2014-04-24 Ole Andersson , Hoshang Heydari

In this paper we introduce a geometric framework for mixed quantum states based on a K\"ahler structure. The geometric framework includes a symplectic form, an almost complex structure, and a Riemannian metric that characterize the space of…

Quantum Physics · Physics 2015-06-09 Hoshang Heydari

The application of geometry to physics has provided us with new insightful information about many physical theories such as classical mechanics, general relativity, and quantum geometry (quantum gravity). The geometry also plays an…

Quantum Physics · Physics 2015-06-19 Hoshang Heydari

Geometrical structures of quantum mechanics provide us with new insightful results about the nature of quantum theory. In this work we consider mixed quantum states represented by finite rank density operators. We review our geometrical…

Quantum Physics · Physics 2015-06-23 Hoshang Heydari , Ole Andersson

In this paper we propose a geometrization of the non-relativistic quantum mechanics for mixed states. Our geometric approach makes use of the Uhlmann's principal fibre bundle to describe the space of mixed states and as a novelty tool, to…

Mathematical Physics · Physics 2015-06-12 Vicent Gimeno , Jose Sotoca

In this paper we use symplectic reduction in an Uhlmann bundle to construct a principal fiber bundle over a general space of unitarily equivalent mixed quantum states. The bundle, which generalizes the Hopf bundle for pure states, gives in…

Quantum Physics · Physics 2014-04-24 Ole Andersson , Hoshang Heydari

An operator generalisation of the notion of geometric phase has been recently proposed purely based on physical grounds. Here we provide a mathematical foundation for its existence, while uncovering new geometrical structures in quantum…

Quantum Physics · Physics 2023-12-25 Vivek M. Vyas

The manifold of pure quantum states is a complex projective space endowed with the unitary-invariant geometry of Fubini and Study. According to the principles of geometric quantum mechanics, the detailed physical characteristics of a given…

Quantum Physics · Physics 2015-06-26 Dorje C. Brody , Lane P. Hughston

A new definition and interpretation of geometric phase for mixed state cyclic unitary evolution in quantum mechanics are presented. The pure state case is formulated in a framework involving three selected Principal Fibre Bundles, and the…

Quantum Physics · Physics 2009-11-10 S. Chaturvedi , E. Ercolessi , G. Marmo , G. Morandi , N. Mukunda , R. Simon

Geometric phase has found a broad spectrum of applications in both classical and quantum physics, such as condensed matter and quantum computation. In this paper we introduce an operational geometric phase for mixed quantum states, based on…

Quantum Physics · Physics 2013-12-11 Ole Andersson , Hoshang Heydari

A geometrical characterization of robustly separable (that is, remaining separable under sufficiently small variiations) mixed states of a bipartite quantum system is given. It is shown that the density matrix of any such state can be…

Quantum Physics · Physics 2007-05-23 Roman R. Zapatrin

We examine the geodesic between two mixed states of arbitrary dimension by means of their geometric mean operator. We utilize the fiber bundle approach by which the distance between two mixed state density operators $\rho_1$ and $\rho_2$ in…

Quantum Physics · Physics 2024-04-08 Paul M. Alsing , Carlo Cafaro , Shannon Ray

This paper presents an introduction to geometric representations of quantum states in which each distinct quantum state, pure and mixed, corresponds to a unique point in a Euclidean space. Beginning with a review of some underappreciated…

Quantum Physics · Physics 2026-02-17 Athanasios Kostikas , Yaroslav Valchyshen , Paul Cadden-Zimansky

The geometric properties of quantum states are crucial for understanding many physical phenomena in quantum mechanics, condensed matter physics, and optics. The central object describing these properties is the quantum geometric tensor,…

Mathematical Physics · Physics 2026-01-21 Marius A. Oancea , Thomas B. Mieling , Giandomenico Palumbo

The quantum geometric tensor (QGT) is a fundamental quantity for characterizing the geometric properties of quantum states and plays an essential role in elucidating various physical phenomena. The traditional QGT, defined only for pure…

Quantum Physics · Physics 2025-07-02 Qianyi Wang , Ben Wang , Jun Wang , Lijian Zhang

Multi-qubit graph states generated by the action of controlled phase shift operators on a separable quantum state of a system, in which all the qubits are in arbitrary identical states, are examined. The geometric measure of entanglement of…

Quantum Physics · Physics 2022-03-11 Kh. P. Gnatenko , N. A. Susulovska

Usually models for quantum computations deal with unitary gates on pure states. In this paper we generalize the usual model. We consider a model of quantum computations in which the state is an operator of density matrix and the gates are…

Quantum Physics · Physics 2007-05-23 Vasily E. Tarasov

A quantum system's state is identified with a density matrix. Though their probabilistic interpretation is rooted in ensemble theory, density matrices embody a known shortcoming. They do not completely express an ensemble's physical…

Quantum Physics · Physics 2021-06-30 Fabio Anza , James P. Crutchfield

We consider a geometrization, i.e., we identify geometrical structures, for the space of density states of a quantum system. We also provide few comments on a possible application of this geometrization for composite systems.

Quantum Physics · Physics 2009-11-11 V. I. Man'ko , G. Marmo , E. C. G. Sudarshan , F. Zaccaria

The method of geometric quantization is applied to a particle moving on an arbitrary Riemannian manifold $Q$ in an external gauge field, that is a connection on a principal $H$-bundle $N$ over $Q$. The phase space of the particle is a…

High Energy Physics - Theory · Physics 2015-06-26 M. A. Robson
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