English
Related papers

Related papers: Geometry of quantum systems: density states and en…

200 papers

Characterization of mixed quantum states represented by density operator is one of the most important task in quantum information processing. In this work we will present a geometric approach to characterize the density operator in terms of…

Quantum Physics · Physics 2017-11-08 Hoshang Heydari

Generalized coherent states provide a means of connecting square integrable representations of a semi-simple Lie group with the symplectic geometry of some of its homogeneous spaces. In the first part of the present work this point of view…

High Energy Physics - Theory · Physics 2015-06-26 Amine M. El Gradechi , Luis M. Nieto

We present a geometrical description of the space of density states of a quantum system of finite dimension. After presenting a brief summary of the geometrical formulation of Quantum Mechanics, we proceed to describe the space of density…

Quantum Physics · Physics 2007-07-26 J. Clemente-Gallardo , G. Marmo

This article is an expository account aimed at viewing entanglement in finite-dimensional quantum many-body systems as a phenomenon of global geometry. While the mathematics of general quantum states has been studied extensively, this…

Quantum Physics · Physics 2026-01-28 Kazuki Ikeda

We study the quantum entanglement structure of integer quantum Hall states via the reduced density matrix of spatial subregions. In particular, we examine the eigenstates, spectrum and entanglement entropy (EE) of the density matrix for…

Strongly Correlated Electrons · Physics 2021-03-17 Benoit Sirois , Lucie Maude Fournier , Julien Leduc , William Witczak-Krempa

Physical constraints such as positivity endow the set of quantum states with a rich geometry if the system dimension is greater than two. To shed some light on the complicated structure of the set of quantum states, we consider a…

Quantum Physics · Physics 2007-05-23 S. G. Schirmer , T. Zhang , J. V. Leahy

The theory of geometric quantum mechanics describes a quantum system as a Hamiltonian dynamical system with a complex projective Hilbert space as its phase space, thus equipped with a Riemannian metric in addition to a symplectic structure.…

Mathematical Physics · Physics 2017-10-26 Barbara A. Sanborn

Quantifying entanglement is a work in progress which is important for the active field of quantum information and computation. A measure of bipartite pure state entanglement is proposed here, named entanglement coherence, which is…

Quantum Physics · Physics 2022-02-15 Neha Pathania , Tabish Qureshi

Tensor networks impose a notion of geometry on the entanglement of a quantum system. In some cases, this geometry is found to reproduce key properties of holographic dualities, and subsequently much work has focused on using tensor networks…

Strongly Correlated Electrons · Physics 2017-10-04 Katharine Hyatt , James R. Garrison , Bela Bauer

We study geometrical aspects of entanglement, with the Hilbert--Schmidt norm defining the metric on the set of density matrices. We focus first on the simplest case of two two-level systems and show that a ``relativistic'' formulation leads…

Quantum Physics · Physics 2013-05-29 Jon Magne Leinaas , Jan Myrheim , Eirik Ovrum

The set of quantum states consists of density matrices of order $N$, which are hermitian, positive and normalized by the trace condition. We analyze the structure of this set in the framework of the Euclidean geometry naturally arising in…

Quantum Physics · Physics 2016-05-17 Ingemar Bengtsson , Stephan Weis , Karol Życzkowski

A finite dimensional quantum mechanical system is modeled by a density rho, a trace one, positive semi-definite matrix on a suitable tensor product space H[N] . For the system to demonstrate experimentally certain non-classical behavior,…

Quantum Physics · Physics 2007-05-23 Arthur O. Pittenger , Morton H. Rubin

Quantization identifies the cotangent bundle of projective space with the (non-Hermitian) rank-$1$ projections of a Hilbert space. We use this identification to study the natural geometric structures of these cotangent bundles and those of…

Symplectic Geometry · Mathematics 2025-03-14 Joshua Lackman

A quantum system can be entirely described by the K\"ahler structure of the projective space P(H) associated to the Hilbert space H of possible states; this is the so-called geometrical formulation of quantum mechanics. In this paper, we…

Differential Geometry · Mathematics 2012-02-07 Mathieu Molitor

Entanglement is defined for each vector subspace of the tensor product of two finite-dimensional Hilbert spaces, by applying the notion of operator entanglement to the projection operator onto that subspace. The operator Schmidt…

Quantum Physics · Physics 2009-11-10 A. J. Bracken

The aim of the paper is to propose geometric descriptions of multipartite entangled states using algebraic geometry. In the context of this paper, geometric means each stratum of the Hilbert space, corresponding to an entangled state, is an…

Mathematical Physics · Physics 2013-02-12 Frédéric Holweck , Jean-Gabriel Luque , Jean-Yves Thibon

Can a secret be hidden not in which quantum state is prepared, but in the way that state \emph{moves} through its space of possibilities? Motivated by this question, we propose an essential geometric perspective on quantum cryptography in…

Quantum Physics · Physics 2025-12-01 Loris Di Cairano

We develop a novel approach to Quantum Mechanics that we call Curved Quantum Mechanics. We introduce an infinite-dimensional K\"ahler manifold ${\cal M}$, that we call the state manifold, such that the cotangent space $T_z^*{\cal M}$ is a…

Quantum Physics · Physics 2024-12-12 Ivan G. Avramidi , Roberto Niardi

The degree to which a pure quantum state is entangled can be characterized by the distance or angle to the nearest unentangled state. This geometric measure of entanglement, already present in a number of settings [A. Shimony, Ann. NY.…

Quantum Physics · Physics 2007-05-23 Tzu-Chieh Wei , Paul M. Goldbart

In the past decades, quantum entanglement has been recognized to be the basic resource in quantum information theory. A fundamental need is then the understanding its qualification and its quantification: Is the quantum state entangled, and…

Quantum Physics · Physics 2013-02-20 Szilárd Szalay