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arXiv 2203.01540math.PR
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大多数瞬时随机游动都有无穷多个截时

Most transient random walks have infinitely many cut times

Noah Halberstam, Tom Hutchcroft

摘要:

证明了如果$(X_n)_{n\geq 0}$是一个瞬态图上的随机游动,使得格林函数沿随机游动至少多项式衰减,则$(X_n)_{n\geq 0}$几乎必然有无穷多个割次.这一条件特别适用于谱维数严格大于$2$的任何图。事实上,我们的证明适用于一般的(可能是不可逆的)马尔可夫链满足类似的格林函数的衰减条件,是尖锐的生灭链。我们推断,猜想Diaconis和弗里德曼(安。1980)持有相同类的马尔可夫链,并解决了猜想Benjamini,Gurel-Gurevich,和Schramm(Ann. Probab. 2011)关于正速度的随机游动存在无穷多个截时。

英文摘要:

We prove that if $(X_n)_{n\geq 0}$ is a random walk on a transient graph such that the Green's function decays at least polynomially along the random walk, then $(X_n)_{n\geq 0}$ has infinitely many cut times almost surely. This condition applies in particular to any graph of spectral dimension strictly larger than $2$. In fact, our proof applies to general (possibly nonreversible) Markov chains satisfying a similar decay condition for the Green's function that is sharp for birth-death chains. We deduce that a conjecture of Diaconis and Freedman (Ann. Probab. 1980) holds for the same class of Markov chains, and resolve a conjecture of Benjamini, Gurel-Gurevich, and Schramm (Ann. Probab. 2011) on the existence of infinitely many cut times for random walks of positive speed.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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