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

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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 (see Shimony 1995 and…

Quantum Physics · Physics 2009-11-10 Tzu-Chieh Wei , Paul M. Goldbart

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

The motion of a quantum particle constrained to a two-dimensional non-compact Riemannian manifold with non-trivial metric can be described by a flat-space Schroedinger-type equation at the cost of introducing local mass and metric and…

Mesoscale and Nanoscale Physics · Physics 2025-12-19 Benjamin Schwager , Theresa Appel , Jamal Berakdar

There exists a remarkable four-qutrit state that carries absolute maximal entanglement in all its partitions. Employing this state, we construct a tensor network that delivers a holographic many body state, the H-code, where the physical…

Quantum Physics · Physics 2015-02-25 Jose I. Latorre , German Sierra

In this work, the definition of the density operator on quantum states in Hilbert spaces and some of its aspects relevant in thermodynamics and information-theoretical entropy calculations are given. In this framework, a physical model…

Mathematical Physics · Physics 2017-09-25 Isiaka Aremua , Mahouton Norbert Hounkonnou , Ezinvi Baloitcha

We study constant mean curvature graphs in the Riemannian 3-dimensional Heisenberg spaces ${\cal H}={\cal H}(\tau)$. Each such ${\cal H}$ is the total space of a Riemannian submersion onto the Euclidean plane $\mathbb{R}^2$ with geodesic…

Differential Geometry · Mathematics 2008-03-03 Luis J. Alias , Marcos Dajczer , Harold Rosenberg

We describe an explicit mechanism for the emergence of a dynamical holographic bulk from the structure of entanglement in a quantum state. We start with a generic system in complete isolation, assuming it has a classical limit involving…

High Energy Physics - Theory · Physics 2020-06-25 Josh Kirklin

The entanglement entropy of the ground state of a quantum lattice model with local interactions usually satisfies an area law. However, in 1D systems some violations may appear in inhomogeneous systems or in random systems. In our…

Quantum Physics · Physics 2018-05-08 Giovanni Ramírez

We introduce a class of generalized geometric measures of entanglement. For pure quantum states of $N$ elementary subsystems, they are defined as the distances from the sets of $K$-separable states ($K=2,...,N$). The entire set of…

Quantum Physics · Physics 2009-07-02 M. Blasone , F. Dell'Anno , S. De Siena , F. Illuminati

We describe the implications of permutation symmetry for the state space and dynamics of quantum mechanical systems of matrices of general size $N$. We solve the general 11- parameter permutation invariant quantum matrix harmonic oscillator…

High Energy Physics - Theory · Physics 2022-12-14 George Barnes , Adrian Padellaro , Sanjaye Ramgoolam

The density matrix formalism which is widely used in the theory of measurements, quantum computing, quantum description of chemical and biological systems always imply the averaging over the states of the environment. In practice this is…

Quantum Physics · Physics 2007-05-23 M. V. Altaisky

We provide a group theory approach to coherent states describing quantum space-time and its properties. This provides a relativistic framework for the metric of a Riemmanian space with bosonic and fermionic coordinates, its continuum and…

General Relativity and Quantum Cosmology · Physics 2023-12-20 Diego J. Cirilo-Lombardo , Norma G. Sanchez

We present a technique to coarse-grain quantum states in a finite-dimensional Hilbert space. Our method is distinguished from other approaches by not relying on structures such as a preferred factorization of Hilbert space or a preferred…

Quantum Physics · Physics 2018-03-16 Ashmeet Singh , Sean M. Carroll

We study various topological invariants on a torsional geometry in the presence of a totally anti-symmetric torsion H under the closed condition dH = 0, which appears in string theory compactification scenarios. By using the identification…

High Energy Physics - Theory · Physics 2008-11-26 Tetsuji Kimura

Entanglement is an important concept in quantum information, quantum communication, and quantum computing. We provide a geometrical analysis of entanglement and separability for all the rank-2 quantum mixed states: complete analysis for the…

Quantum Physics · Physics 2017-03-09 Michel Boyer , Rotem Liss , Tal Mor

A particularly simple description of separability of quantum states arises naturally in the setting of complex algebraic geometry, via the Segre embedding. This is a map describing how to take products of projective Hilbert spaces. In this…

Quantum Physics · Physics 2020-08-24 Joana Cirici , Jordi Salvadó , Josep Taron

Using the natural connection equivalent to the SU(2) Yang-Mills instanton on the quaternionic Hopf fibration of $S^7$ over the quaternionic projective space ${\bf HP}^1\simeq S^4$ with an $SU(2)\simeq S^3$ fiber the geometry of entanglement…

Quantum Physics · Physics 2008-11-26 Peter Levay

A complete description of the multitudinous ways in which quantum particles can be entangled requires the use of high-dimensional abstract mathematical spaces. We report here a particularly interesting feature of the nine-dimensional convex…

Quantum Physics · Physics 2011-04-01 Paul B. Slater

We use the natural lifts of the fundamental tensor field g to the cotangent bundle T*M of a Riemannian manifold (M,g), in order to construct an almost Hermitian structure (G,J) of diagonal type on T*M. The obtained almost complex structure…

Differential Geometry · Mathematics 2007-05-23 Vasile Oproiu , Dumitru Daniel Porosniuc

We show that any decoherence functional $D$ can be represented by a spanning vector-valued measure on a complex Hilbert space. Moreover, this representation is unique up to an isomorphism when the system is finite. We consider the natural…

Quantum Physics · Physics 2022-09-01 Stan Gudder