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Related papers: Fractional Revival and Association Schemes

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We consider the continuous-time quantum walk defined on the adjacency matrix of a graph. At each instant, the walk defines a mixing matrix which is doubly-stochastic. The average of the mixing matrices contains relevant information about…

Combinatorics · Mathematics 2017-09-13 Gabriel Coutinho , Chris Godsil , Krystal Guo , Hanmeng Zhan

Fiol has characterized quotient-polynomial graphs as precisely the connected graphs whose adjacency matrix generates the adjacency algebra of a symmetric association scheme. We show that a collection of non-negative integer parameters of…

Combinatorics · Mathematics 2024-04-11 Allen Herman , Roghayeh Maleki

In order to extract correlation information inherited in stochastic time series, the visibility graph algorithm has been recently proposed, by which a time series can be mapped onto a complex network. We demonstrate that the visibility…

Data Analysis, Statistics and Probability · Physics 2016-05-24 Pouya Manshour

A communication network can be modeled as a directed connected graph with edge weights that characterize performance metrics such as loss and delay. Network tomography aims to infer these edge weights from their pathwise versions measured…

Combinatorics · Mathematics 2018-12-05 Gregory Berkolaiko , Nick Duffield , Mahmood Ettehad , Kyriakos Manousakis

We study the entanglement dynamics of discrete time quantum walks acting on bounded finite sized graphs. We demonstrate that, depending on system parameters, the dynamics may be monotonic, oscillatory but highly regular, or quasi-periodic.…

Quantum Physics · Physics 2012-03-07 Peter P. Rohde , Alessandro Fedrizzi , Timothy C. Ralph

For a spatial characteristic, there exist commonly fat-tail frequency distributions of fragment-size and -mass of glass, areas enclosed by city roads, and pore size/volume in random packings. In order to give a new analytical approach for…

Statistical Mechanics · Physics 2015-06-12 Yukio Hayashi , Takayuki Komaki , Yusuke Ide , Takuya Machida , Norio Konno

Graph structures are ubiquitous throughout the natural sciences. Here we consider graph-structured quantum data and describe how to carry out its quantum machine learning via quantum neural networks. In particular, we consider training data…

Quantum Physics · Physics 2021-03-22 Kerstin Beer , Megha Khosla , Julius Köhler , Tobias J. Osborne

We study the properties of random graphs where for each vertex a {\it neighbourhood} has been previously defined. The probability of an edge joining two vertices depends on whether the vertices are neighbours or not, as happens in Small…

Disordered Systems and Neural Networks · Physics 2009-11-10 Sebastian Risau-Gusman

In many areas such as computational biology, finance or social sciences, knowledge of an underlying graph explaining the interactions between agents is of paramount importance but still challenging. Considering that these interactions may…

Signal Processing · Electrical Eng. & Systems 2021-04-29 Mircea Moscu , Ricardo A. Borsoi , Cédric Richard , José-Carlos M. Bermudez

In contrast to the usual quantum systems which have at most a finite number of open spectral gaps if they are periodic in more than one direction, periodic quantum graphs may have gaps arbitrarily high in the spectrum. This property of…

Quantum Physics · Physics 2020-05-26 Pavel Exner , Ondřej Turek

Graph partitioning problems emerge in a wide variety of complex systems, ranging from biology to finance, but can be rigorously analyzed and solved only for a few graph ensembles. Here, an ensemble of equitable graphs, i.e. random graphs…

Social and Information Networks · Computer Science 2017-10-25 Paolo Barucca

Inference and optimization of real-value edge variables in sparse graphs are studied using the Bethe approximation and replica method of statistical physics. Equilibrium states of general energy functions involving a large set of real…

Disordered Systems and Neural Networks · Physics 2009-11-11 K. Y. Michael Wong , D. Saad

This paper proposes fractional order graph neural networks (FGNNs), optimized by the approximation strategy to address the challenges of local optimum of classic and fractional graph neural networks which are specialised at aggregating…

Machine Learning · Computer Science 2021-07-07 Zijian Liu , Chunbo Luo , Shuai Li , Peng Ren , Geyong Min

We develop the theory of pretty good fractional revival in quantum walks on graphs using their Laplacian matrices as the Hamiltonian. We classify the paths and the double stars that have Laplacian pretty good fractional revival.

Combinatorics · Mathematics 2022-09-20 Ada Chan , Bobae Johnson , Mengzhen Liu , Malena Schmidt , Zhanghan Yin , Hanmeng Zhan

In the branch of mathematics known as graph theory, graphs are considered as a set of points, called vertices, with connections between these points, called edges. The purpose of this paper is to study mappings between two graphs that have…

Combinatorics · Mathematics 2019-03-19 Jeffrey Beyerl , Cameron Sharpe

Network representation learning has exploded recently. However, existing studies usually reconstruct networks as sequences or matrices, which may cause information bias or sparsity problem during model training. Inspired by a cognitive…

Machine Learning · Computer Science 2019-10-01 Jie Bai , Linjing Li , Daniel Zeng

This paper introduces a new graph construction, the permutational power of a graph, whose adjacency matrix is obtained by the composition of a permutation matrix with the adjacency matrix of the graph. It is shown that this construction…

Combinatorics · Mathematics 2019-10-29 Matteo Cavaleri , Daniele D'Angeli , Alfredo Donno

The connection between certain entangled states and graphs has been heavily studied in the context of measurement-based quantum computation as a tool for understanding entanglement. Here we show that this correspondence can be harnessed in…

Quantum Physics · Physics 2016-03-23 Liming Zhao , Carlos A. Pérez-Delgado , Joseph F. Fitzsimons

Iterative phase retrieval algorithms typically employ projections onto constraint subspaces to recover the unknown phases in the Fourier transform of an image, or, in the case of x-ray crystallography, the electron density of a molecule.…

Numerical Analysis · Mathematics 2025-10-20 Veit Elser

Fractal geometry, defined by self-similar patterns across scales, is crucial for understanding natural structures. This work addresses the fractal inverse problem, which involves extracting fractal codes from images to explain these…

Graphics · Computer Science 2025-02-25 Adarsh Djeacoumar , Felix Mujkanovic , Hans-Peter Seidel , Thomas Leimkühler