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arXiv · 2609.06641

Recurrence, Transience, and the Rate of Escape for Elephant Random Walks with Two Memory Channels

Abstract

We study the one-dimensional elephant random walk with two memory channels introduced by Saha [Phys.\ Rev.\ E \textbf{106}, L062105 (2022)] with memory parameter $p\in(0,1)$. Maulik, Roy and Sadhukhan [arXiv:2509.10225] proved recurrence for $p\le11/16$ and transience for $p>7/8$, leaving the range $11/16<p\le7/8$ open. We close this gap by proving that $p=11/16$ is the exact recurrence--transience threshold and by determining how fast the walk escapes from the origin throughout the transient regime. For $11/16<p<7/8$, we also show that the scaling limit obtained by Maulik, Roy and Sadhukhan is almost surely nonzero. At $p=7/8$, we prove that the walk is transient with zero asymptotic velocity and escapes at the scale $n/\sqrt{\log n}$.

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BibTeXRIS

Ngo Phuoc Nguyen Ngoc. 2026-09-06. Recurrence, Transience, and the Rate of Escape for Elephant Random Walks with Two Memory Channels. https://arxiv.org/abs/2609.06641

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