PPolySim OS

Abelian Sandpile

Add sand one grain at a time and chaos organizes itself. When a pile gets too steep it topples, triggering avalanches of every size — the birth of self-organized criticality.

Abelian SandpileLive

Controls

Grains drop on the center cell. When a cell reaches 4 grains it topples, sending one to each neighbor — which can trigger chain-reaction avalanches. The pile self-organizes into an intricate fractal at the critical slope.

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Data Inspector

Grains added0
Last avalanche0
Topple at4 grains

Governing equation

Reading this result: The pile is still filling toward its critical slope; once cells reach 4 grains, chain-reaction topples begin.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

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How it works

In the Bak-Tang-Wiesenfeld sandpile, each cell topples when it holds four or more grains, distributing one to each neighbor. Toppling can cascade into avalanches whose sizes follow a power law. The final stable configurations form strikingly intricate fractal patterns.

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Frequently asked questions

Is this abelian sandpile model tool really free?▾
Yes. Abelian Sandpile runs entirely in your browser using your device's own compute, so local use is free forever. You only pay Compute Tokens if you scale a job to the cloud.
Do I need to install anything?▾
No. Everything runs client-side in a modern browser — no downloads, no license, no account required to start.
Can I save or share my simulation?▾
Create a free account to save projects, and use a shareable embed or minted DOI to publish a live, interactive version anywhere.
How accurate are the results?▾
The solver uses established numerical methods, but results are for research and educational purposes and should be validated against experiment or professional review before you rely on them.