Past exam of the mathematics course of the University of Cambridge 2016 iii Paper 204 2 d Solution Created 2026-10-03 Updated 2026-10-06
Write for the deterministic set of -step self-avoiding walks from . Each uses distinct edges, so independence givesFor , the function on is a concave function. The Jensen inequality gives the root-moment bound for open self-avoiding walksEquivalently, the Lyapunov moment inequality compares exponents and , both strictly positive. Taking the limit superior and the connective constant limit provesThis includes and . No independence between the different self-avoiding walk indicators is asserted or needed.