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Related papers: Unitary Shift Operators on a Graph

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A finite dimensional operator that commutes with some symmetry group admits quotient operators, which are determined by the choice of associated representation. Taking the quotient isolates the part of the spectrum supporting the chosen…

Mathematical Physics · Physics 2023-11-30 Ram Band , Gregory Berkolaiko , Christopher H. Joyner , Wen Liu

Vertex based and spectral based GSP sampling has been studied recently. The literature recognizes that methods in one domain do not have a counterpart in the other domain. This paper shows that in fact one can develop a unified graph signal…

Signal Processing · Electrical Eng. & Systems 2022-06-29 John Shi , Jose M. F. Moura

Learning-based MIMO detection has shown strong empirical performance, yet existing methods typically rely on fixed-depth architectures without explicitly modeling the progressive refinement of symbol estimates. In this paper, we revisit…

Information Theory · Computer Science 2026-05-04 Nan Jiang , Jiadong Hong , Lei Liu , Xinyu Bian , Wenjie Wang , Zhaoyang Zhang

Recently, Gutman defined a new vertex-degree-based graph invariant, named the Sombor index $SO$ of a graph $G$, and is defined by $$SO(G)=\sum_{uv\in E(G)}\sqrt{d_G(u)^2+d_G(v)^2},$$ where $d_G(v)$ is the degree of the vertex $v$ of $G$. In…

Combinatorics · Mathematics 2023-09-26 Batmend Horoldagva , Chunlei Xu

In graph signal processing, one of the most important subjects is the study of filters, i.e., linear transformations that capture relations between graph signals. One of the most important families of filters is the space of shift invariant…

Signal Processing · Electrical Eng. & Systems 2022-09-29 Feng Ji , See Hian Lee , Wee Peng Tay

A large number of applications in wireless sensor networks include projecting a vector of noisy observations onto a subspace dictated by prior information about the field being monitored. In general, accomplishing such a task in a…

Signal Processing · Electrical Eng. & Systems 2021-04-28 Siavash Mollaebrahim , Baltasar Beferull-Lozano

In classic graph signal processing, given a real-valued graph signal, its graph Fourier transform is typically defined as the series of inner products between the signal and each eigenvector of the graph Laplacian. Unfortunately, this…

Machine Learning · Computer Science 2022-01-12 Fanchao Meng , Mark Orr , Samarth Swarup

We propose a sampling theory for signals that are supported on either directed or undirected graphs. The theory follows the same paradigm as classical sampling theory. We show that perfect recovery is possible for graph signals bandlimited…

Information Theory · Computer Science 2016-11-15 Siheng Chen , Rohan Varma , Aliaksei Sandryhaila , Jelena Kovačević

We propose the Interferometric Graph Transform (IGT), which is a new class of deep unsupervised graph convolutional neural network for building graph representations. Our first contribution is to propose a generic, complex-valued spectral…

Machine Learning · Computer Science 2020-06-11 Edouard Oyallon

Fourier transform (FT) plays a crucial role in a broad range of applications, from enhancement, restoration and analysis through to security, compression and manipulation. The Fourier transform (FT) is a process that converts a function…

Numerical Analysis · Mathematics 2023-05-05 Benjamin Kenwright

We introduce a novel harmonic analysis for functions defined on the vertices of a strongly connected directed graph of which the random walk operator is the cornerstone. As a first step, we consider the set of eigenvectors of the random…

Functional Analysis · Mathematics 2021-11-02 Harry Sevi , Gabriel Rilling , Pierre Borgnat

We establish several new relations between the discrete transition operator, the continuous Laplacian and the averaging operator associated with combinatorial and metric graphs. It is shown that these operators can be expressed through each…

Spectral Theory · Mathematics 2016-03-11 Daniel Lenz , Konstantin Pankrashkin

We review quantum chaos on graphs. We construct a unitary operator which represents the quantum evolution on the graph and study its spectral and wavefunction statistics. This operator is the analogue of the classical evolution operator on…

Chaotic Dynamics · Physics 2007-05-23 Tsampikos Kottos

Graph Transformers (GTs) have demonstrated remarkable performance in graph representation learning over popular graph neural networks (GNNs). However, self--attention, the core module of GTs, preserves only low-frequency signals in graph…

Machine Learning · Computer Science 2025-05-30 Guoguo Ai , Guansong Pang , Hezhe Qiao , Yuan Gao , Hui Yan

A versatile method is described for the practical computation of the discrete Fourier transforms (DFT) of a continuous function $g(t)$ given by its values $g_{j}$ at the points of a uniform grid $F_{N}$ generated by conjugacy classes of…

Mathematical Physics · Physics 2009-11-10 A. Atoyan , J. Patera

This paper develops fast graph Fourier transform (GFT) algorithms with O(n log n) runtime complexity for rank-one updates of the path graph. We first show that several commonly-used audio and video coding transforms belong to this class of…

Signal Processing · Electrical Eng. & Systems 2024-09-16 Samuel Fernández-Menduiña , Eduardo Pavez , Antonio Ortega

As graph representations of data emerge in multiple domains, data analysts need to be able to intelligently select among a magnitude of different data graphs based on the effects different graph operators have on them. Exhaustive execution…

Social and Information Networks · Computer Science 2018-08-21 Tasos Bakogiannis , Ioannis Giannakopoulos , Dimitrios Tsoumakos , Nectarios Koziris

This paper provides a description of the spectrum of diagonal perturbation of weighted shift operator acting on a separable Hilbert space.

Functional Analysis · Mathematics 2018-01-23 M. L. Sahari , A. K. Taha , L. Randriamihamison

Building upon our previous work, on graphical representation of a quantum state by signless Laplacian matrix, we pose the following question. If a local unitary operation is applied to a quantum state, represented by a signless Laplacian…

Quantum Physics · Physics 2016-07-29 Supriyo Dutta , Bibhas Adhikari , Subhashish Banerjee

This paper introduces a $\textit{canonical}$ graph signal model defined by a $\textit{canonical}$ graph and a $\textit{canonical}$ shift, the $\textit{companion}$ graph and the $\textit{companion}$ shift. These are canonical because, under…

Signal Processing · Electrical Eng. & Systems 2022-03-28 John Shi , Jose M. F. Moura