Title
Phase Transition for Glauber Dynamics for Independent Sets on Regular Trees.
Abstract
We study the effect of boundary conditions on the relaxation time of the Glauber dynamics for the hardcore lattice gas model on the n-vertex regular b-ary tree of height h. The hard-core model is defined on independent sets weighted by an activity (or fugacity) λ on trees. Reconstruction studies the effect of a 'typical' boundary condition, i.e., fixed assignment to the leaves, on the root. The threshold for when reconstruction occurs (and a typical boundary influences the root in the limit h → ∞) has been of considerable recent interest since it appears to be connected to the efficiency of certain local algorithms on locally tree-like graphs. The reconstruction threshold occurs at ω ≈ ln b/b where λ = ω(1 + ω)b is a convenient re-parameterization of the model. We prove that for all boundary conditions, the relaxation time τ in the non-reconstruction region is fast, namely τ = O (n1+ob(1)) for any ω ≤ ln b/b. In the reconstruction region, for all boundary conditions, we prove τ = O (n1+δ+ob(1)) for ω = (1 + ω) ln b/b, for every δ 0. In contrast, we construct a boundary condition, for which the Glauber dynamics slows down in the reconstruction region, namely τ = Ω (n1+δ-ob(1)) for ω = (1 + δ) ln b/b, for every δ 0. The interesting part of our proof is this lower bound result, which uses a general technique that transforms an algorithm to prove reconstruction into a set in the state space of the Glauber dynamics with poor conductance.
Year
DOI
Venue
2010
10.1137/120885498
Clinical Orthopaedics and Related Research
Keywords
DocType
Volume
boundary condition,non-reconstruction region,reconstruction study,glauber dynamic,hardcore lattice gas model,phase transition,reconstruction threshold,typical boundary,hard-core model,reconstruction region,regular tree,independent set,relaxation time,lower bound,state space,distributed computing,randomized algorithms,leader election
Journal
28
Issue
ISSN
ISBN
2
0895-4801
978-1-61197-251-1
Citations 
PageRank 
References 
2
0.40
21
Authors
5
Name
Order
Citations
PageRank
Ricardo Restrepo120.74
Daniel Stefankovic224328.65
Juan C. Vera3507.98
Eric Vigoda474776.55
Linji Yang5585.17