Applications of Mathematics ( IF 0.6 ) Pub Date : 2020-09-04 , DOI: 10.21136/am.2020.0362-19 Balaji Ramamurthy , Ravindra Bhalchandra Bapat , Shivani Goel
Let T be a tree with n vertices. To each edge of T we assign a weight which is a positive definite matrix of some fixed order, say, s. Let Dij denote the sum of all the weights lying in the path connecting the vertices i and j of T. We now say that Dij is the distance between i and j. Define D ≔ [Dij], where Dii is the s × s null matrix and for i ≠ j, Dij is the distance between i and j. Let G be an arbitrary connected weighted graph with n vertices, where each weight is a positive definite matrix of order s. If i and j are adjacent, then define Lij ≔ − W−1ij , where Wij is the weight of the edge (i, j). Define \({L_{ii}}: = \sum\limits_{i \ne j,j = 1}^n {W_{ij}^{ - 1}}.\) The Laplacian of G is now the ns × ns block matrix L ≔ [Lij]. In this paper, we first note that D−1 − L is always nonsingular and then we prove that D and its perturbation (D−1 − L)−1 have many interesting properties in common.
中文翻译:
拉普拉斯算子扰动的距离矩阵
令T为具有n个顶点的树。我们为T的每个边缘分配一个权重,该权重是某个固定阶数的正定矩阵,例如s。让d IJ表示所有躺在路连接顶点的权重的总和我和Ĵ的牛逼。现在我们说D ij是i和j之间的距离。定义d ≔[ d IJ ],其中d II是小号×小号零矩阵和用于我≠ Ĵ,dij是i和j之间的距离。令G为具有n个顶点的任意连通加权图,其中每个权重为阶s的正定矩阵。如果i和j相邻,则定义L ij -W -1 ij ,其中W ij是边缘( i,j)的权重。定义\({L_ {ii}}:= \ sum \ limits_ {i \ ne j,j = 1} ^ n {W_ {ij} ^ {-1}}。\)G的拉普拉斯算子现在是ns× ns块矩阵L [ Lij ]。在本文中,我们首先要注意d -1 -大号总是奇异的,然后我们证明了d及其扰动( d -1 -大号) -1有许多共同的有趣的性质。