Abstract:
Three characteristics of two-dimensional uniform spanning trees are
nontrivially related to one another{:} the average density of a sandpile,
the looping constant of a square lattice, and the return probability of a loop-erased random walk. We briefly trace the long history of the discovery
of their unexpected rational values.
Keywords:Abelian sandpile model, loop-erased random walk, monomer–dimer model.