Loading...
Search for: laplacian-eigenvalues-of-graphs
0.011 seconds

    The algebraic connectivity of a graph and its complement

    , Article Linear Algebra and Its Applications ; Volume 555 , 2018 , Pages 157-162 ; 00243795 (ISSN) Afshari, B ; Akbari, S ; Moghaddamzadeh, M. J ; Mohar, B ; Sharif University of Technology
    Elsevier Inc  2018
    Abstract
    For a graph G, let λ2(G) denote its second smallest Laplacian eigenvalue. It was conjectured that λ2(G)+λ2(G‾)≥1, where G‾ is the complement of G. In this paper, it is shown that max⁡{λ2(G),λ2(G‾)}≥[Formula presented]. © 2018 Elsevier Inc  

    Some results on the Laplacian spread conjecture

    , Article Linear Algebra and Its Applications ; Volume 574 , 2019 , Pages 22-29 ; 00243795 (ISSN) Afshari, B ; Akbari, S ; Sharif University of Technology
    Elsevier Inc  2019
    Abstract
    For a graph G of order n, let λ 2 (G) denote its second smallest Laplacian eigenvalue. It was conjectured that λ 2 (G)+λ 2 (G‾)≥1, where G‾ is the complement of G. For any x∈R n , let ∇ x ∈R (n2) be the vector whose {i,j}-th entry is |x i −x j |. In this paper, we show the aforementioned conjecture is equivalent to prove that every two orthonormal vectors f,g∈R n with zero mean satisfy ‖∇ f −∇ g ‖ 2 ≥2. In this article, it is shown that for the validity of the conjecture it suffices to prove that the conjecture holds for all permutation graphs. © 2019 Elsevier Inc  

    A note on the algebraic connectivity of a graph and its complement

    , Article Linear and Multilinear Algebra ; 2019 ; 03081087 (ISSN) Afshari, B ; Akbari, S ; Sharif University of Technology
    Taylor and Francis Ltd  2019
    Abstract
    For a graph G, let λ2(G) denote its second smallest Laplacian eigenvalue. It was conjectured that (Formula presented.), where (Formula presented.) is the complement of G. In this paper, it is shown that (Formula presented.). © 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group  

    A note on the algebraic connectivity of a graph and its complement

    , Article Linear and Multilinear Algebra ; 2019 ; 03081087 (ISSN) Afshari, B ; Akbari, S
    Taylor and Francis Ltd  2019
    Abstract
    For a graph G, let λ2(G) denote its second smallest Laplacian eigenvalue. It was conjectured that (Formula presented.), where (Formula presented.) is the complement of G. In this paper, it is shown that (Formula presented.). © 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group  

    A note on the algebraic connectivity of a graph and its complement

    , Article Linear and Multilinear Algebra ; Volume 69, Issue 7 , 2021 , Pages 1248-1254 ; 03081087 (ISSN) Afshari, B ; Akbari, S ; Sharif University of Technology
    Taylor and Francis Ltd  2021
    Abstract
    For a graph G, let (Formula presented.) denote its second smallest Laplacian eigenvalue. It was conjectured that (Formula presented.), where (Formula presented.) is the complement of G. In this paper, it is shown that (Formula presented.). © 2019 Informa UK Limited, trading as Taylor & Francis Group  

    A note on the algebraic connectivity of a graph and its complement

    , Article Linear and Multilinear Algebra ; Volume 69, Issue 7 , 2021 , Pages 1248-1254 ; 03081087 (ISSN) Afshari, B ; Akbari, S ; Sharif University of Technology
    Taylor and Francis Ltd  2021
    Abstract
    For a graph G, let (Formula presented.) denote its second smallest Laplacian eigenvalue. It was conjectured that (Formula presented.), where (Formula presented.) is the complement of G. In this paper, it is shown that (Formula presented.). © 2019 Informa UK Limited, trading as Taylor & Francis Group