z-logo
Premium
Eigenvalues of K 1 , k ‐Free Graphs and the Connectivity of Their Independence Complexes
Author(s) -
Aharoni Ron,
Alon Noga,
Berger Eli
Publication year - 2016
Publication title -
journal of graph theory
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.164
H-Index - 54
eISSN - 1097-0118
pISSN - 0364-9024
DOI - 10.1002/jgt.22004
Subject(s) - mathematics , combinatorics , independence number , eigenvalues and eigenvectors , induced subgraph , graph , degree (music) , laplace operator , independence (probability theory) , discrete mathematics , laplacian matrix , vertex (graph theory) , mathematical analysis , statistics , physics , quantum mechanics , acoustics
Let G be a graph on n vertices, with maximal degree d , and not containing K 1 , kas an induced subgraph. We prove: 1.λ ( G ) ≤ ( 2 − 1 2 k − 2 + o ( 1 ) ) d2.η ( I ( G ) ) ≥ n ( k − 1 ) d ( 2 k − 3 ) + k − 1 .Here λ ( G ) is the maximal eigenvalue of the Laplacian of G , I ( G ) is the independence complex of G , and η ( C ) denotes the topological connectivity of a complex C plus 2. These results provide improved bounds for the existence of independent transversals in K 1 , k ‐free graphs.

This content is not available in your region!

Continue researching here.

Having issues? You can contact us here
Accelerating Research

Address

John Eccles House
Robert Robinson Avenue,
Oxford Science Park, Oxford
OX4 4GP, United Kingdom