Anthony Bonato ; William B. Kinnersley ; Pawel Pralat - Toppling numbers of complete and random graphs

dmtcs:2084 - Discrete Mathematics & Theoretical Computer Science, November 18, 2014, Vol. 16 no. 3 -
Toppling numbers of complete and random graphsArticle

Authors: Anthony Bonato 1; William B. Kinnersley 2; Pawel Pralat 1

  • 1 Department of Mathematics [Ryerson University - Toronto]
  • 2 Department of Mathematics (Rhode Island, Kingston)

We study a two-person game played on graphs based on the widely studied chip-firing game. Players Max and Min alternately place chips on the vertices of a graph. When a vertex accumulates as many chips as its degree, it fires, sending one chip to each neighbour; this may in turn cause other vertices to fire. The game ends when vertices continue firing forever. Min seeks to minimize the number of chips played during the game, while Max seeks to maximize it. When both players play optimally, the length of the game is the toppling number of a graph G, and is denoted by t(G). By considering strategies for both players and investigating the evolution of the game with differential equations, we provide asymptotic bounds on the toppling number of the complete graph. In particular, we prove that for sufficiently large n 0.596400 n2 < t(Kn) < 0.637152 n2. Using a fractional version of the game, we couple the toppling numbers of complete graphs and the binomial random graph G(n,p). It is shown that for pn ≥n² / √ log(n) asymptotically almost surely t(G(n,p))=(1+o(1)) p t(Kn).

Volume: Vol. 16 no. 3
Section: Graph Theory
Published on: November 18, 2014
Submitted on: March 12, 2013
Keywords: chip-firing game,toppling game,Abelian sandpile model,[INFO.INFO-DM] Computer Science [cs]/Discrete Mathematics [cs.DM]

1 Document citing this article

Consultation statistics

This page has been seen 437 times.
This article's PDF has been downloaded 293 times.