# Diffusion limited aggregation in the Boolean lattice

## TL;DR

This paper investigates a diffusion-limited aggregation process on the Boolean lattice, proving that lower levels fill up and an unbounded path forms, providing rigorous results for a model analogous to classical DLA.

## Contribution

It introduces and analyzes a new DLA model on the Boolean lattice, establishing rigorous results about level filling and path formation.

## Key findings

- Lower levels of the lattice become fully occupied.
- An isolated unbounded path from the origin to the top forms.
- The process terminates with a unique unbounded path.

## Abstract

In the Diffusion Limited Aggregation (DLA) process on on $\mathbb{Z}^2$, or more generally $\mathbb{Z}^d$, particles aggregate to an initially occupied origin by arrivals on a random walk. The scaling limit of the result, empirically, is a fractal with dimension strictly less than $d$. Very little has been shown rigorously about the process, however. We study an analogous process on the Boolean lattice $\{0,1\}^n$, in which particles take random decreasing walks from $(1,\dots,1)$, and stick at the last vertex before they encounter an occupied site for the first time; the vertex $(0,\dots,0)$ is initially occupied. In this model, we can rigorously prove that lower levels of the lattice become full, and that the process ends by producing an isolated path of unbounded length reaching $(1,\dots,1)$.