English

Modeling Random Walks to Infinity on Primes in $\mathbb{Z}[\sqrt{2}]$

Number Theory 2022-01-31 v2

Abstract

An interesting question, known as the Gaussian moat problem, asks whether it is possible to walk to infinity on Gaussian primes with steps of bounded length. Our work examines a similar situation in the real quadratic integer ring Z[2]\mathbb{Z}[\sqrt{2}] whose primes cluster near the asymptotes y=±x/2y = \pm x/\sqrt{2} as compared to Gaussian primes, which cluster near the origin. We construct a probabilistic model of primes in Z[2]\mathbb{Z}[\sqrt{2}] by applying the prime number theorem and a combinatorial theorem for counting the number of lattice points whose absolute values of their norms are at most r2r^2. We then prove that it is impossible to walk to infinity if the walk remains within some bounded distance from the asymptotes. Lastly, we perform a few moat calculations to show that the longest walk is likely to stay close to the asymptotes; hence, we conjecture that there is no walk to infinity on Z[2]\mathbb{Z}[\sqrt{2}] primes with steps of bounded length.

Keywords

Cite

@article{arxiv.2011.07386,
  title  = {Modeling Random Walks to Infinity on Primes in $\mathbb{Z}[\sqrt{2}]$},
  author = {Bencheng Li and Steven J. Miller and Tudor Popescu and Daniel Sarnecki and Nawapan Wattanawanichkul},
  journal= {arXiv preprint arXiv:2011.07386},
  year   = {2022}
}

Comments

21 pages, 12 figures, from Walking to Infinity Polymath REU

R2 v1 2026-06-23T20:13:27.663Z