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Related papers: Quantum chromatic numbers via operator systems

200 papers

We formulate and study, in general terms, the problem of quantum system identification, i.e., the determination (or estimation) of unknown quantum channels through their action on suitably chosen input density operators. We also present a…

Quantum Physics · Physics 2007-05-23 Maxim Raginsky

We use multi-time correlation functions of quantum systems to construct random variables with statistical properties that reflect the degree of complexity of the underlying quantum dynamics.

Quantum Physics · Physics 2009-10-31 F. Benatti , M. Fannes

In this work, we study the $\delta$-chromatic number of a graph which is the chromatic number of the $\delta$-complement of a graph. We give a structure of the $\delta$-complements and sharp bounds on the $\delta$-chromatic numbers of the…

Combinatorics · Mathematics 2024-01-02 Wipawee Tangjai , Witsarut Pho-on , Panupong Vichitkunakorn

Using coherent states in optical quantum process tomography is a practically-relevant approach. Here, we develop a framework for complete characterization of quantum-optical processes in terms of normally-ordered moments by using coherent…

Quantum Physics · Physics 2017-04-11 M. Ghalaii , A. T. Rezakhani

Motivated from the theory of quantum error correcting codes, we investigate a combinatorial problem that involves a symmetric $n$-vertices colourable graph and a group of operations (colouring rules) on the graph: find the minimum sequence…

Combinatorics · Mathematics 2014-09-10 German Luna , Samuel Reid , Bianca De Sanctis , Vlad Gheorghiu

We bring together in one place some of the main results and applications from our recent works in quantum information theory, in which we have brought techniques from operator theory, operator algebras, and graph theory for the first time…

Quantum Physics · Physics 2021-10-18 Comfort Mintah , David W. Kribs , Michael Nathanson , Rajesh Pereira

A new algorithm to obtain the chromatic number of a finite, connected graph is proposed in this paper. The algorithm is based on contraction of non adjacent vertices.

Discrete Mathematics · Computer Science 2019-10-16 Athma. M. Ram , R. Rama

In this work, we try to enunciate the Total chromatic number of some Cayley graphs like the Cayley graph on Symmetric group, Alternating group, Dihedral group with respect to some generating sets and some other regular graphs.

Combinatorics · Mathematics 2023-07-04 Prajnanaswaroopa S

We establish a second anti-blocker theorem for non-commutative convex corners, show that the anti-blocking operation is continuous on bounded sets of convex corners, and define optimisation parameters for a given convex corner that…

Operator Algebras · Mathematics 2024-09-25 Gareth Boreland , Ivan G. Todorov , Andreas Winter

Conventional Ramsey-theoretic investigations for edge-colourings of complete graphs are framed around avoidance of certain configurations. Motivated by considerations arising in the field of Qualitative Reasoning, we explore edge colourings…

Combinatorics · Mathematics 2022-01-11 Badriah Al Juaid , Marcel Jackson , James Koussas , Tomasz Kowalski

We introduce the characteristic numbers and the chromatic polynomial of a tensor. Our approach generalizes and unifies the chromatic polynomial of a graph and of a matroid, characteristic numbers of quadrics in Schubert calculus, Betti…

Algebraic Geometry · Mathematics 2021-11-02 Austin Conner , Mateusz Michałek

In this paper we describe and thoroughly discuss three reported experiments in quantum optics (QO) involving interferometers and non-linear crystals. We show that by using a graphical method and an over-simplified model of the parametric…

Optics · Physics 2015-02-16 Stefan Ataman

We introduce the concept of regular quantum graphs and construct connected quantum graphs with discrete symmetries. The method is based on a decomposition of the quantum propagator in terms of permutation matrices which control the way…

Chaotic Dynamics · Physics 2007-06-13 Simone Severini , Gregor Tanner

This work studies how a suitably-designed classical system generates with a quantum-like (QL) state space mediated by a graph. The graph plays a special dual role by directing the topology of the classical network and defining a state space…

Quantum Physics · Physics 2026-03-24 Gregory D. Scholes

In the broad range of studies related to quantum graphs, quantum graph spectra appear as a topic of special interest. They are important in the context of diffusion type problems posed on metric graphs. Theoretical findings suggest that…

Numerical Analysis · Mathematics 2023-12-15 Chong-Son Dröge , Anna Weller

A fundamental problem in quantum information is to describe efficiently multipartite quantum states. An efficient representation in terms of graphs exists for several families of quantum states (graph, cluster, stabilizer states),…

Quantum Physics · Physics 2012-07-04 Radu Ionicioiu , Tim P. Spiller

We provide a graphical method to describe and analyze non-Gaussian quantum states using a hypergraph framework. These states are pivotal resources for quantum computing, communication, and metrology, but their characterization is hindered…

Quantum Physics · Physics 2025-07-28 Lina Vandré , Boxuan Jing , Yu Xiang , Otfried Gühne , Qiongyi He

This paper introduces an efficient quantum computing method for reducing special graphs in the context of the graph coloring problem. The special graphs considered include both symmetric and non-symmetric graphs where the axis passes…

Quantum Physics · Physics 2025-10-21 Lord Sen , Shyamapada Mukherjee

We introduce two generalizations of Kochen-Specker (KS) sets: projective KS sets and generalized KS sets. We then use projective KS sets to characterize all graphs for which the chromatic number is strictly larger than the quantum chromatic…

Quantum Physics · Physics 2013-07-24 Laura Mancinska , Giannicola Scarpa , Simone Severini

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