Zobrazeno 1 - 10
of 102
pro vyhledávání: '"MULAS, RAFFAELLA"'
Autor:
Beers, Lies, Mulas, Raffaella
For a graph with largest normalized Laplacian eigenvalue $\lambda_N$ and (vertex) coloring number $\chi$, it is known that $\lambda_N\geq \chi/(\chi-1)$. Here we prove properties of graphs for which this bound is sharp, and we study the multiplicity
Externí odkaz:
http://arxiv.org/abs/2402.09160
Autor:
Mulas, Raffaella
We consider two different notions of graph colouring, namely, the $t$-periodic colouring for vertices that has been introduced in 1974 by Bondy and Simonovits, and the periodic colouring for oriented edges that has been recently introduced in the con
Externí odkaz:
http://arxiv.org/abs/2307.10910
Autor:
Devriendt, Karel, Mulas, Raffaella
We give new characterizations for the class of uniformly dense matroids and study applications of these characterizations to graphic and real representable matroids. We show that a matroid is uniformly dense if and only if its base polytope contains
Externí odkaz:
http://arxiv.org/abs/2306.15267
We prove new properties of the non-backtracking graph and the non-backtracking Laplacian for graphs. In particular, among other results, we prove that two simple graphs are isomorphic if and only if their corresponding non-backtracking graphs are iso
Externí odkaz:
http://arxiv.org/abs/2303.00373
Autor:
Mulas, Raffaella, Zucal, Giulio
Inspired by the notion of action convergence in graph limit theory, we introduce a measure-theoretic representation of matrices, and we use it to define a new notion of pseudo-metric on the space of matrices. Moreover, we show that such pseudo-metric
Externí odkaz:
http://arxiv.org/abs/2208.07246
Autor:
Mulas, Raffaella, Nie, Jiaxi
Publikováno v:
Acta Mathematica Hungarica (2023)
We introduce the following simpler variant of the Tur\'an problem: Given integers $n>k>r\geq 2$ and $m\geq 1$, what is the smallest integer $t$ for which there exists an $r$-uniform hypergraph with $n$ vertices, $t$ edges and $m$ connected components
Externí odkaz:
http://arxiv.org/abs/2207.10052
Publikováno v:
Discrete Mathematics, 346(10):113536 (2023)
We introduce a non-backtracking Laplace operator for graphs and we investigate its spectral properties. With the use of both theoretical and computational techniques, we show that the spectrum of this operator captures several structural properties o
Externí odkaz:
http://arxiv.org/abs/2203.10824
Publikováno v:
Journal of Graph Theory, 2023
We prove that, for any connected graph on $N\geq 3$ vertices, the spectral gap from the value $1$ with respect to the normalized Laplacian is at most $1/2$. Moreover, we show that equality is achieved if and only if the graph is either a petal graph
Externí odkaz:
http://arxiv.org/abs/2110.08751
We develop a general theory of random walks on hypergraphs which includes, as special cases, the different models that are found in literature. In particular, we introduce and analyze general random walk Laplacians for hypergraphs, and we compare the
Externí odkaz:
http://arxiv.org/abs/2106.11663
Autor:
Mulas, Raffaella
Hypergraphs are a generalization of graphs in which edges can connect any number of vertices. They allow the modeling of complex networks with higher-order interactions, and their spectral theory studies the qualitative properties that can be inferre
Externí odkaz:
http://arxiv.org/abs/2106.04827