English
Related papers

Related papers: A Graph-Theoretic Approach to Quantum Measurement …

200 papers

In this paper we introduce a nonextensive quantum information theoretic measure which may be defined between any arbitrary number of density matrices, and we analyze its fundamental properties in the spectral graph-theoretic framework.…

Information Theory · Computer Science 2015-04-15 A. Ben Hamza

Graph-based tests are a class of non-parametric two-sample tests useful for analyzing high-dimensional data. The test statistics are constructed from similarity graphs (such as K-minimum spanning tree), and consequently, their performance…

Methodology · Statistics 2025-06-23 Yichuan Bai , Lynna Chu

Understanding causal relationships among the variables of a system is paramount to explain and control its behavior. For many real-world systems, however, the true causal graph is not readily available and one must resort to predictions…

Machine Learning · Statistics 2024-12-20 Elias Eulig , Atalanti A. Mastakouri , Patrick Blöbaum , Michaela Hardt , Dominik Janzing

Incompatibility of quantum measurements is of fundamental importance in quantum mechanics. It is closely related to many nonclassical phenomena such as Bell nonlocality, quantum uncertainty relations, and quantum steering. We study the…

Quantum Physics · Physics 2020-01-01 Lin Zhang , Hua Xiang , Xianqing Li-Jost , Shao-Ming Fei

We investigate the notion of quantumness based on the non-commutativity of the algebra of observables and introduce a measure of quantumness based on the mutual incompatibility of quantum states. We show that such a quantity can be…

Quantum graphs are commonly used as models of complex quantum systems, for example molecules, networks of wires, and states of condensed matter. We consider quantum statistics for indistinguishable spinless particles on a graph,…

Mathematical Physics · Physics 2011-01-11 JM Harrison , JP Keating , JM Robbins

Incompatible, i.e. non-jointly measurable quantum measurements are a necessary resource for many information processing tasks. It is known that increasing the number of distinct measurements usually enhances the incompatibility of a…

Quantum Physics · Physics 2023-09-28 Lucas Tendick , Hermann Kampermann , Dagmar Bruß

Three notions of complementarity - operational, probabilistic, and value complementarity - are reanalysed with respect to the question of joint measurements and compared with reference to some examples of canonically conjugate observables.…

Quantum Physics · Physics 2011-01-04 P. Busch , P. J. Lahti

This paper addresses the ubiquity of remarkable measures on graphs, and their applications. In many queueing systems, it is necessary to take into account the compatibility constraints between users, or between supply and demands, and so…

Probability · Mathematics 2021-11-29 Jocelyn Begeot , Irène Marcovici , Pascal Moyal

The measurability by means of continuous measurements, of an observable $\A(t_0)$, at an instant, and of a time averaged observable, $\bar \A=1/T\int \A(t')dt'$, is examined for linear and in particular for non-linear quantum mechanical…

Quantum Physics · Physics 2007-05-23 Y. Aharonov , B. Reznik

Let $G=(V,E)$ be a finite, combinatorial graph. We define a notion of curvature on the vertices $V$ via the inverse of the resistance distance matrix. We prove that this notion of curvature has a number of desirable properties. Graphs with…

Combinatorics · Mathematics 2023-02-22 Karel Devriendt , Andrea Ottolini , Stefan Steinerberger

A measure-scaling quasi-isometry between two connected graphs is a quasi-isometry that is quasi-$\kappa$-to-one in a natural sense for some $\kappa>0$. For non-amenable graphs, all quasi-isometries are quasi-$\kappa$-to-one for any…

Group Theory · Mathematics 2021-05-12 Anthony Genevois , Romain Tessera

Determining the measurement uncertainty region is a difficult problem for generic sets of observables. For this reason the literature on exact measurement uncertainty regions is focused on symmetric sets of observables, where the symmetries…

Quantum Physics · Physics 2019-09-12 Oliver Reardon-Smith

Quantum graphs are defined by having a Laplacian defined on the edges of a metric graph with boundary conditions on each vertex such that the resulting operator, $\mathbf{L}$, is self-adjoint. We use Neumann boundary conditions although we…

Spectral Theory · Mathematics 2025-12-02 Mats-Erik Pistol

We investigate the role of symmetric quantum cloning machines (QCMs) in quantifying the mutual incompatibility of quantum observables. Specifically, we identify a cloning-based incompatibility measure whereby the incompatibility of a set of…

Quantum Physics · Physics 2021-09-20 Arindam Mitra , Prabha Mandayam

In 1995, Brouwer proved that the toughness of a connected $k$-regular graph $G$ is at least $k/\lambda-2$, where $\lambda$ is the maximum absolute value of the non-trivial eigenvalues of $G$. Brouwer conjectured that one can improve this…

Combinatorics · Mathematics 2013-12-10 Sebastian M. Cioabă , Wiseley Wong

A (molecular) graph in which all vertices have the same degree is known as a regular graph. According to Gutman, Hansen, and M\'elot [J. Chem. Inf. Model. 45 (2005) 222-230], it is of interest to measure the irregularity of nonregular…

Combinatorics · Mathematics 2025-01-06 Akbar Ali , Darko Dimitrov , Tamás Réti , Abeer M. Albalahi , Amjad E. Hamza

The topic of measurement in relativistic quantum field theory is addressed in this article. Some of the long standing problems of this subject are highlighted, including the incompatibility of an instantaneous ``collapse of the…

Mathematical Physics · Physics 2024-11-21 Christopher J. Fewster , Rainer Verch

A central challenge in quantum metrology is identifying optimal measurements that saturate the quantum Cramer-Rao bound under realistic constraints, e.g., local measurements. We show that symmetries of the probe state provide a general…

Quantum Physics · Physics 2026-03-10 Jia-Xuan Liu , Hai-Long Shi , Chunfeng Wu , Sixia Yu

We determine the optimum topology of quasi-one dimensional nonlinear optical structures using generalized quantum graph models. Quantum graphs are relational graphs endowed with a metric and a multiparticle Hamiltonian acting on the edges,…

Quantum Physics · Physics 2015-06-19 Rick Lytel , Shoresh Shafei , Mark G. Kuzyk
‹ Prev 1 4 5 6 7 8 10 Next ›