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Related papers: Probing the geometry of two-qubit state space by e…

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Mapping the system evolution of a two-state system allows the determination of the effective system Hamiltonian directly. We show how this can be achieved even if the system is decohering appreciably over the observation time. A method to…

We propose a new approach to the geometry of the four-qubit entanglement classes depending on parameters. More precisely, we use invariant theory and algebraic geometry to describe various stratifications of the Hilbert space by SLOCC…

Mathematical Physics · Physics 2017-03-08 Frédéric Holweck , Jean-Garbriel Luque , Jean-Yves Thibon

It is shown that the geometric measure of entanglement of a pure multipartite state satisfies a polynomial equation, generalising the characteristic equation of the matrix of coefficients of a bipartite state. The equation is solved for a…

Quantum Physics · Physics 2010-07-06 Joseph J. Hilling , Anthony Sudbery

We consider the simplest identical-fermion system that exhibits the phenomenon of entanglement (beyond exchange correlations) to analyze its speed of evolution towards an orthogonal state, and revisit the relation between this latter and…

Quantum Physics · Physics 2022-10-05 Sahory Canseco J. , Andrea Valdés-Hernández

We give an explicit expression for the geometric measure of entanglement for three qubit states that are linear combinations of four orthogonal product states. It turns out that the geometric measure for these states has three different…

Quantum Physics · Physics 2008-09-03 Levon Tamaryan , DaeKil Park , Jin-Woo Son , Sayatnova Tamaryan

One of the key features of information geometry in the classical setting is the existence of a metric structure and a family of connections on the space of probability distributions. The uniqueness of the Fisher--Rao metric and the duality…

Quantum Physics · Physics 2025-07-25 Kunal Pal

This is a review of the geometry of quantum states using elementary methods and pictures. Quantum states are represented by a convex body, often in high dimensions. In the case of n-qubits, the dimension is exponentially large in n. The…

Quantum Physics · Physics 2019-08-12 Joseph Avron , Oded Kenneth

Quantum Hall effects provide intuitive ways of revealing the topology in crystals, i.e., each quantized "step" represents a distinct topological state. Here, we seek a counterpart for "visualizing" quantum geometry, which is a broader…

Quantum Physics · Physics 2025-01-10 B. Q. Song , J. D. H. Smith , T. Jiang , Y. X. Yao , J. Wang

We consider a classically chaotic system that is described by a Hamiltonian H(Q,P;x), where (Q,P) describes a particle moving inside a cavity, and x controls a deformation of the boundary. The quantum-eigenstates of the system are |n(x)>.…

Chaotic Dynamics · Physics 2009-10-31 Doron Cohen , Alex Barnett , Eric J. Heller

We investigate the question of unitarity of evolution between hypersurfaces in quantum field theory in curved spacetime from the perspective of the general boundary formulation. Unitarity thus means unitarity of the quantum operator that…

High Energy Physics - Theory · Physics 2011-08-25 Daniele Colosi , Robert Oeckl

The manifold of ground states of a family of quantum Hamiltonians can be endowed with a quantum geometric tensor whose singularities signal quantum phase transitions and give a general way to define quantum phases. In this paper, we show…

Quantum Physics · Physics 2020-05-29 Davide Rattacaso , Alioscia Hamma , Patrizia Vitale

In this series of papers we aim to provide a mathematically comprehensive framework to the Hamiltonian pictures of quantum field theory in curved spacetimes. Our final goal is to study the kinematics and the dynamics of the theory from the…

Quantum states defined over a parameter space form a Grassmann manifold. To capture the geometry of the associated gauge structure, gauge-invariant quantities are essential. We employ the projector of a multilevel system to quantify the…

Mesoscale and Nanoscale Physics · Physics 2025-10-30 Shin-Ming Huang , Dimitrios Giataganas

We study the quantum dynamics of a particle confined in a twisted tube with a linearly varying cross section. By relating a general linear transformation matrix to the system's Hamiltonian, we use an extended thin-layer method to derive an…

Quantum Physics · Physics 2025-09-03 Guo-Hua Liang , Ai-Guo Mei , Men-Yun Lai , Shu-Sheng Xu

We investigate the differential geometry of bipartite quantum states. In particular the manifold structures of pure bipartite states are studied in detail. The manifolds with respect to all normalized pure states of arbitrarily given…

Quantum Physics · Physics 2009-11-13 Zuhuan Yu , Xianqing Jost-Li , Qingzhong Li , Jintao Lv , Shao-Ming Fei

We investigate entanglement in two-qubit systems using a geometric representation based on the minimum of essential parameters. The latter is achieved by requiring subsystems with the same entropy, regardless of whether the state of the…

Quantum Physics · Physics 2024-12-24 Salvio Luna-Hernandez , Claudia Quintana , Oscar Rosas-Ortiz

Geometric phases, arising from cyclic evolutions in a curved parameter space, appear in a wealth of physical settings. Recently, and largely motivated by the need of an experimentally realistic definition for quantum computing applications,…

Quantum Physics · Physics 2011-02-04 F. M. Cucchietti , J. -F. Zhang , F. C. Lombardo , P. I. Villar , R. Laflamme

We develop a means of simulating the evolution and measurement of a multipartite quantum state under discrete or continuous evolution using another quantum system with states and operators lying in a real Hilbert space. This extends…

Quantum Physics · Physics 2009-10-26 Matthew McKague , Michele Mosca , Nicolas Gisin

We use the free evolution propagator to determine the quantum probability representation (i.e., the general expression of the tomogram) of any one-dimensional system described by a density state. The evolution operator for the considered…

Linear dynamics restricted to invariant submanifolds generally gives rise to nonlinear dynamics. Submanifolds in the quantum framework may emerge for several reasons: one could be interested in specific properties possessed by a given…