Title
The genus of the Erdős‐Rényi random graph and the fragile genus property
Abstract
We investigate the genus g(n, m) of the Erdos-Renyi random graph G(n, m), providing a thorough description of how this relates to the function m = m(n), and finding that there is different behavior depending on which "region" m falls into. Results already exist for m <= n/2+O(n(2/3)) and m = omega(n(1+1/j)) for j is an element of N, and so we focus on the intermediate cases. We establish that g(n, m) = (1 + o(1)) m/2 whp (with high probability) when n << m = n(1+o(1)), that g(n, m) = (1 + o(1)) mu(lambda)m whp for a given function mu(lambda) when m similar to lambda n for lambda > 1/2, and that g(n, m) = (1+o(1)) 8s(3)/3n(2) whp when m = n/2 + s for n(2/3) << s << n. We then also show that the genus of a fixed graph can increase dramatically if a small number of random edges are added. Given any connected graph with bounded maximum degree, we find that the addition of epsilon n edges will whp result in a graph with genus Omega(n), even when epsilon is an arbitrarily small constant! We thus call this the "fragile genus" property.
Year
DOI
Venue
2020
10.1002/rsa.20871
RANDOM STRUCTURES & ALGORITHMS
Keywords
Field
DocType
fragile genus,genus,random graphs
Discrete mathematics,Combinatorics,Random graph,Mathematics
Journal
Volume
Issue
ISSN
56.0
1.0
1042-9832
Citations 
PageRank 
References 
0
0.34
0
Authors
3
Name
Order
Citations
PageRank
Chris Dowden154.26
Mihyun Kang216329.18
michael krivelevich31688179.90