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The minimal Bures distance of a quantum state of a bipartite system AB to the set of classical states for subsystem A defines a geometric measure of quantum discord. When A is a qubit, we show that this geometric quantum discord is given in…

Quantum Physics · Physics 2013-12-24 Dominique Spehner , Miguel Orszag

We consider the geometry of quantum states associated with different classes of random matrix Hamiltonians, in particular ensembles that show integrability to chaotic transition in terms of the nearest neighbour energy level spacing…

Quantum Physics · Physics 2025-09-03 Ankit Gill , Keun-Young Kim , Kunal Pal , Kuntal Pal

Nielsen, et al. [1, 2] proposed a view of quantum computation where determining optimal algorithms is equivalent to extremizing a geodesic length or cost functional. This view of optimization is highly suggestive of an action principle of…

Quantum Physics · Physics 2012-08-17 Jonathan R. McDonald , Paul M. Alsing , Howard A. Blair

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

Spin networks in loop quantum gravity provide a kinematical picture of quantum geometry but lack a natural mechanism for dynamical Dirac-type evolution, while the Wheeler--DeWitt equation typically enters only as an imposed constraint. We…

General Relativity and Quantum Cosmology · Physics 2025-11-04 Partha Nandi , Partha Ghose , Francesco Petruccione

Time-independent Hamiltonian flows are viewed as geodesic flows in a curved manifold, so that the onset of chaos hinges on properties of the curvature two-form entering into the Jacobi equation. Attention focuses on ensembles of orbit…

Astrophysics · Physics 2009-10-30 Henry E. Kandrup

Localized one-particle states of a quantum field theory--whether in flat space or on a curved background--are expected to exhibit geodesic motion in an appropriate semiclassical regime. This expectation is often invoked heuristically: in…

High Energy Physics - Theory · Physics 2026-05-08 Vaibhav Burman , Chethan Krishnan , Livesh Parajuli

The study of quantum walks has been shown to have a wide range of applications in areas such as artificial intelligence, the study of biological processes, and quantum transport. The quantum stochastic walk, which allows for incoherent…

Quantum Physics · Physics 2020-02-20 Luke C. G. Govia , Bruno G. Taketani , Peter K. Schuhmacher , Frank K. Wilhelm

We examine evolutions where each component of a given decomposition of a mixed quantal state evolves independently in a unitary fashion. The geometric phase and parallel transport conditions for this type of decomposition dependent…

Quantum Physics · Physics 2018-02-09 David Kult , Erik Sjöqvist

Quantum measurements are described as instantaneous projections in textbooks. They can be stretched out in time using weak measurements, whereby one can observe the evolution of a quantum state as it heads towards one of the eigenstates of…

Quantum Physics · Physics 2018-04-11 Parveen Kumar , Suman Kundu , Madhavi Chand , R. Vijayaraghavan , Apoorva Patel

This manuscript gathers and subsumes a long series of works on using QW to simulate transport phenomena. Quantum Walks (QWs) consist of single and isolated quantum systems, evolving in discrete or continuous time steps according to a…

Quantum Physics · Physics 2021-12-23 Giuseppe Di Molfetta

Geometric and holonomic quantum computation utilizes intrinsic geometric properties of quantum-mechanical state spaces to realize quantum logic gates. Since both geometric phases and quantum holonomies are global quantities depending only…

Quantum Physics · Physics 2023-08-03 Jiang Zhang , Thi Ha Kyaw , Stefan Filipp , Leong-Chuan Kwek , Erik Sjöqvist , Dianmin Tong

This paper considers the control landscape of quantum transitions in multi-qubit systems driven by unitary transformations with single-qubit interaction terms. The two-qubit case is fully analyzed to reveal the features of the landscape…

Quantum Physics · Physics 2009-10-09 Renan Cabrera , Herschel Rabitz

This work presents a unified perspective on thermal equilibrium and quantum dynamics by examining the simplest quantum system, a qubit, as a minimal model. We show that both the thermal partition function and the Loschmidt amplitude can be…

Quantum Physics · Physics 2026-03-02 Manmeet Kaur , Somendra M. Bhattacharjee

The quantum description of time evolution in non-linear gravitational systems such as cosmological space-times is not well understood. We show, in the simplified setting of mini-superspace, that time evolution of this system can be obtained…

General Relativity and Quantum Cosmology · Physics 2023-05-02 Anne-Katherine Burns , David E. Kaplan , Tom Melia , Surjeet Rajendran

Quantum computers are important examples of processes whose evolution can be described in terms of iterations of single step operators or their adjoints. Based on this, Hamiltonian evolution of processes with associated step operators $T$…

Quantum Physics · Physics 2009-10-30 Paul Benioff

In an amended version of non-Hermitian interaction picture we propose to work with the states $\psi(t)$ in a dyadic representation. The control of evolution via two conjugate Schr\"{o}diner equations then renders the usual necessity of the…

Quantum Physics · Physics 2023-06-29 Miloslav Znojil

Quantum Graphity (QG) is a model of emergent geometry in which space is represented by a dynamical graph. The graph evolves under the action of a Hamiltonian from a high-energy pre-geometric state to a low-energy state in which geometry…

General Relativity and Quantum Cosmology · Physics 2015-10-07 Samuel A. Wilkinson , Andrew D. Greentree

In a wide range of quantum gravity theories, quasiclassical geometries, which are solutions to the Einstein field equations approximately, are described by "coherent states." Here we propose a Hamiltonian formalism for gravitational…

General Relativity and Quantum Cosmology · Physics 2025-12-01 Sijia Wang , Achintya Sajeendran , Dong-han Yeom , Robert B. Mann , Joshua Foo

In many singular metric spaces, the regularity of a shortest-length curve is unknown. Algebraic varieties, or more generally sets defined by finitely many polynomial or real analytic equalities or inequalities, all locally partition into…

Differential Geometry · Mathematics 2023-01-30 Chengcheng Yang