English
Related papers

Related papers: Optimization and complexity of inertia-type bounds…

200 papers

For $k\ge 1$, the $k$-independence number $\alpha_k$ of a graph is the maximum number of vertices that are mutually at distance greater than $k$. The well-known inertia and ratio bounds for the (1-)independence number $\alpha(=\alpha_1)$ of…

Combinatorics · Mathematics 2022-01-14 Aida Abiad , Cristina Dalfó , Miquel Àngel Fiol , Sjanne Zeijlemaker

The inertia bound and ratio bound (also known as the Cvetkovi\'c bound and Hoffman bound) are two fundamental inequalities in spectral graph theory, giving upper bounds on the independence number $\alpha(G)$ of a graph $G$ in terms of…

Combinatorics · Mathematics 2024-07-01 Matthew Kwan , Yuval Wigderson

A well known upper bound for the independence number $\alpha(G)$ of a graph $G$, due to Cvetkovi\'{c}, is that \begin{equation*} \alpha(G) \le n^0 + \min\{n^+ , n^-\} \end{equation*} where $(n^+, n^0, n^-)$ is the inertia of $G$. We prove…

Combinatorics · Mathematics 2021-10-05 Pawel Wocjan , Clive Elphick , Aida Abiad

The $k^{\text{th}}$ power of a graph $G=(V,E)$, $G^k$, is the graph whose vertex set is $V$ and in which two distinct vertices are adjacent if and only if their distance in $G$ is at most $k$. This article proves various eigenvalue bounds…

Combinatorics · Mathematics 2020-10-27 Aida Abiad , Gabriel Coutinho , Miquel Angel Fiol , Bruno Nogueira , Sjanne Zeijlemaker

We present monotonicity inequalities for certain functions involving eigenvalues of $p$-Laplacians on signed graphs with respect to $p$. Inspired by such monotonicity, we propose new spectrum-based graph invariants, called (variational)…

Spectral Theory · Mathematics 2023-11-01 Chuanyuan Ge , Shiping Liu , Dong Zhang

We define the independence ratio and the chromatic number for bounded, self-adjoint operators on an L^2-space by extending the definitions for the adjacency matrix of finite graphs. In analogy to the Hoffman bounds for finite graphs, we…

Functional Analysis · Mathematics 2014-10-07 Christine Bachoc , Evan DeCorte , Fernando Mario de Oliveira Filho , Frank Vallentin

A well known upper bound for the independence number $\alpha(G)$ of a graph $G$, is that \[ \alpha(G) \le n^0 + \min\{n^+ , n^-\}, \] where $(n^+, n^0, n^-)$ is the inertia of $G$. We prove that this bound is also an upper bound for the…

Combinatorics · Mathematics 2018-12-07 Pawel Wocjan , Clive Elphick

This paper generalizes and unifies the existing spectral bounds on the $k$-independence number of a graph, which is the maximum size of a set of vertices at pairwise distance greater than $k$. The previous bounds known in the literature…

Combinatorics · Mathematics 2018-08-28 A. Abiad , G. Coutinho , M. A. Fiol

For a graph $G$, its $k$-th power $G^k$ is constructed by placing an edge between two vertices if they are within distance $k$ of each other. The $k$-independence number $\alpha_k(G)$ is defined as the independence number of $G^k$. By using…

Combinatorics · Mathematics 2024-11-15 Aida Abiad , Jiang Zhou

Graph parameters such as the clique number, the chromatic number, and the independence number are central in many areas, ranging from computer networks to linguistics to computational neuroscience to social networks. In particular, the…

Computational Complexity · Computer Science 2020-12-15 Fabian Frei , Edith Hemaspaandra , Jörg Rothe

For a graph $G$, its $k$-th graph power $G^k$ is constructed by placing an edge between two vertices if they are within distance $k$. We consider the problem of deriving upper bounds on the Shannon capacity of graph powers by using spectral…

Combinatorics · Mathematics 2025-10-21 Aida Abiad , Cristina Dalfó , Miquel Àngel Fiol

The independence gap of a graph was introduced by Ekim et al. (2018) as a measure of how far a graph is from being well-covered. It is defined as the difference between the maximum and minimum size of a maximal independent set. We…

Combinatorics · Mathematics 2018-12-14 Tınaz Ekim , Didem Gözüpek , Ademir Hujdurović , Martin Milanič

A $k$-independent set in a connected graph is a set of vertices such that any two vertices in the set are at distance greater than $k$ in the graph. The $k$-independence number of a graph, denoted $\alpha_k$, is the size of a largest…

Combinatorics · Mathematics 2023-05-01 Lord C. Kavi , Mike Newman

Spectral independence is a recently-developed framework for obtaining sharp bounds on the convergence time of the classical Glauber dynamics. This new framework has yielded optimal $O(n \log n)$ sampling algorithms on bounded-degree graphs…

Data Structures and Algorithms · Computer Science 2023-10-16 Ivona Bezáková , Andreas Galanis , Leslie Ann Goldberg , Daniel Štefankovič

The Hoffman ratio bound, Lov\'{a}sz theta function and Schrijver theta function are classical upper bounds for the independence number of graphs, which are useful in graph theory, extremal combinatorics and information theory. By using…

Combinatorics · Mathematics 2025-02-19 Jiang Zhou

We present quantum complexity lower and upper bounds for independent set problems in graphs. In particular, we give quantum algorithms for computing a maximal and a maximum independent set in a graph. We present applications of these…

Quantum Physics · Physics 2007-05-23 Sebastian Doern

A graph is inductive $k$-independent if there exists and ordering of its vertices $v_{1},...,v_{n}$ such that $\alpha(G[N(v_{i})\cap V_{i}])\leq k $ where $N(v_{i})$ is the neighborhood of $v_{i}$, $V_{i}=\{v_{i},...,v_{n}\}$ and $\alpha$…

Discrete Mathematics · Computer Science 2017-09-21 George Manoussakis

For a graph $G$ with vertex set $V(G)$ and independence number $\alpha(G)$, S. M. Selkow (Discrete Mathematics, 132(1994)363--365) established the famous lower bound $\sum\limits_{v\in…

Combinatorics · Mathematics 2019-11-19 Jochen Harant , Samuel Mohr

In this paper, we obtain two spectral upper bounds for the $k$-independence number of a graph which is is the maximum size of a set of vertices at pairwise distance greater than $k$. We construct graphs that attain equality for our first…

Combinatorics · Mathematics 2016-08-19 Aida Abiad , Sebastian Cioabă , Michael Tait

We introduce a new method for computing bounds on the independence number and fractional chromatic number of classes of graphs with local constraints, and apply this method in various scenarios. We establish a formula that generates a…

Combinatorics · Mathematics 2021-07-26 François Pirot , Jean-Sébastien Sereni
‹ Prev 1 2 3 10 Next ›