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Related papers: Geometry along Evolution of Mixed Quantum States

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In this work, we present a geometrical formulation of quantum thermodynamics based on contact geometry and principal fiber bundles. The quantum thermodynamic state space is modeled as a contact manifold, with equilibrium Gibbs states…

Mathematical Physics · Physics 2026-04-20 Álvaro Tejero , Martín de la Rosa

It is known that there are infinitely many distinguishability metrics for mixed quantum states. This freedom, in turn, leads to metric-dependent interpretations of physically meaningful geometric quantities such as complexity and volume of…

Quantum Physics · Physics 2023-05-31 Paul M. Alsing , Carlo Cafaro , Orlando Luongo , Cosmo Lupo , Stefano Mancini , Hernando Quevedo

The problem of geometric phase for an open quantum system is reinvestigated in a unifying approach. Two of existing methods to define geometric phase, one by Uhlmann's approach and the other by kinematic approach, which have been considered…

Quantum Physics · Physics 2009-11-11 A. T. Rezakhani , P. Zanardi

We study characteristics of quantum evolution which can be called curvature and torsion. The curvature shows a deviation of the state vector in quantum evolution from the geodesic line. The torsion shows a deviation of state vector from the…

Quantum Physics · Physics 2017-04-03 H. P. Laba , V. M. Tkachuk

In presence of dissipation, quantal states may acquire complex-valued phase effects. We suggest a notion of dissipative interferometry that accommodates this complex-valued structure and that may serve as a tool for analyzing the effect of…

Quantum Physics · Physics 2016-08-16 Erik Sjöqvist

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 geometric phases for standard coherent states which are widely used in quantum optics have attracted a large amount of attention. Nevertheless, few physicists consider about the counterparts of non-linear coherent states, which are…

Quantum Physics · Physics 2011-05-24 Da-Bao Yang , Ying Chen , Fu-Lin Zhang , Jing-Ling Chen

The geometry of the $q$-deformed line is studied. A real differential calculus is introduced and the associated algebra of forms represented on a Hilbert space. It is found that there is a natural metric with an associated linear connection…

Quantum Algebra · Mathematics 2014-11-18 B. L. Cerchiai , R. Hinterding , J. Madore , J. Wess

We elucidate the geometry of quantum adiabatic evolution. By minimizing the deviation from adiabaticity we find a Riemannian metric tensor underlying adiabatic evolution. Equipped with this tensor, we identify a unified geometric…

Quantum Physics · Physics 2010-10-28 Ali T. Rezakhani , Damian F. Abasto , Daniel A. Lidar , Paolo Zanardi

The concept of quantum geometry for single-particle states has revolutionized our interpretation of several emergent properties in condensed matter. However, a description of the quantum geometry for interacting particles and an…

Materials Science · Physics 2025-08-12 MingRui Lai , Fengyuan Xuan , Su Ying Quek

We show that it is possible to represent various descriptions of Quantum Mechanics in geometrical terms. In particular we start with the space of observables and use the momentum map associated with the unitary group to provide an unified…

Mathematical Physics · Physics 2008-11-26 J. F. Carinena , J. Clemente-Gallardo , G. Marmo

One of the most celebrated accomplishments of modern physics is the description of fundamental principles of nature in the language of geometry. As the motion of celestial bodies is governed by the geometry of spacetime, the motion of…

Mesoscale and Nanoscale Physics · Physics 2024-09-23 Tianyu Liu , Xiao-Bin Qiang , Hai-Zhou Lu , X. C. Xie

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

When an entangled state evolves under local unitaries, the entanglement in the state remains fixed. Here we show the dynamical phase acquired by an entangled state in such a scenario can always be understood as the sum of the dynamical…

Quantum Physics · Physics 2009-11-13 Mark Williamson , Vlatko Vedral

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

It was shown that quantum mechanical qubit states as elements of two dimensional complex space can be generalized to elements of even subalgebra of geometric (Clifford) algebra over Euclidian space. The construction critically depends on…

General Physics · Physics 2015-09-15 Alexander M. Soiguine

We study the evolution of a spin-s system described by the long-range zz-type Ising interaction. The Fubini-Study metric of the quantum state manifold defined by this evolution is obtained. We explore the topology of this manifold and show…

Quantum Physics · Physics 2019-05-01 Yu. S. Krynytskyi , A. R. Kuzmak

A geometric interpretation for the A-fidelity between two states of a qubit system is presented, which leads to an upper bound of the Bures fidelity. The metrics defined based on the A-fidelity are studied by numerical method. An…

Quantum Physics · Physics 2008-12-30 Zhihao Ma , Fu-Lin Zhang , Jing-Ling Chen

We investigate the evolution of a single qubit subject to a continuous unitary dynamics and an additional interrupting influence which occurs periodically. One may imagine a dynamically evolving closed quantum system which becomes open at…

Quantum Physics · Physics 2009-11-07 Juergen Audretsch , Lajos Diosi , Thomas Konrad

It is known that mixed quantum states are highly entropic states of imperfect knowledge (i.e., incomplete information) about a quantum system, while pure quantum states are states of perfect knowledge (i.e., complete information) with…

Quantum Physics · Physics 2022-11-23 Carlo Cafaro , Paul M. Alsing