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.