Elliptic Harnack Inequality for ${\mathbb{Z}}^d$

Autor: Athreya, Siva, Gadhiwala, Nitya, Radhakrishnan, Ritvik R.
Rok vydání: 2022
Předmět:
Zdroj: Involve 15 (2022) 687-708
Druh dokumentu: Working Paper
DOI: 10.2140/involve.2022.15.687
Popis: We prove the scale invariant Elliptic Harnack Inequality (EHI) for non-negative harmonic functions on ${\mathbb{Z}}^d$. The purpose of this note is to provide a simplified self-contained probabilistic proof of EHI in ${\mathbb{Z}}^d$ that is accessible at the undergraduate level. We use the Local Central Limit Theorem for simple symmetric random walks on ${\mathbb{Z}}^d$ to establish Gaussian bounds for the $n$-step probability function. The uniform Green inequality and the classical Balayage formula then imply the EHI.
Comment: To appear in Involve-a journal of mathematics
Databáze: arXiv