English

Dynamical sensitivity of recurrence and transience of branching random walks

Probability 2009-12-07 v2

Abstract

Consider a sequence of i.i.d. random variables XnX_n where each random variable is refreshed independently according to a Poisson clock. At any fixed time tt the law of the sequence is the same as for the sequence at time 0 but at random times almost sure properties of the sequence may be violated. If there are such \emph{exceptional times} we say that the property is \emph{dynamically sensitive}, otherwise we call it \emph{dynamically stable}. In this note we consider branching random walks on Cayley graphs and prove that recurrence and transience are dynamically stable in the sub-and supercritical regime. While the critical case is left open in general we prove dynamical stability for a specific class of Cayley graphs. Our proof combines techniques from the theory of ranching random walks with those of dynamical percolation.

Keywords

Cite

@article{arxiv.0907.4557,
  title  = {Dynamical sensitivity of recurrence and transience of branching random walks},
  author = {Sebastian Müller},
  journal= {arXiv preprint arXiv:0907.4557},
  year   = {2009}
}

Comments

v2: proofs and presentation revised, corrected the proof for dynamical stability of transience, behaviour in critical case is left open in general but covered for a certain class of Cayley graphs