Site percolation on planar graphs and circle packings
Ron Peled - Tel Aviv University and Princeton University
Location: Hill Center Room 705
Date & time: Monday, 30 January 2023 at 2:00PM - 3:00PM
Abstract: Color each vertex of an infinite graph blue with probability p and red with probability 1-p, independently among vertices. For which values of p is there an infinite connected component of blue vertices? The talk will focus on this classical percolation problem for the class of planar graphs. Recently, Itai Benjamini made several conjectures in this context, relating the percolation problem to the behavior of simple random walk on the graph. We will explain how partial answers to Benjamini's conjectures may be obtained using the theory of circle packings. Among the results is the fact that the critical percolation probability admits a universal lower bound for the class of recurrent plane triangulations. Open problems will be emphasized. No previous knowledge on percolation or circle packings will be assumed.