%0 Journal Article %T A Universal upper bound on Graph Diameter based on Laplacian Eigenvalues %A Shayan Oveis Gharan %A Luca Trevisan %J Computer Science %D 2012 %I arXiv %X We prove that the diameter of any unweighted connected graph G is O(k log n/lambda_k), for any k>= 2. Here, lambda_k is the k smallest eigenvalue of the normalized laplacian of G. This solves a problem posed by Gil Kalai. %U http://arxiv.org/abs/1212.2701v1