Question 1

What is an abelian sandpile?

Accepted Answer

A mathematical model in which grains dropped on a grid topple when a cell exceeds a threshold, cascading into avalanches with striking self-similar patterns. It is abelian because the final pile is the same no matter what order the grains are added in.

Question 2

What is self-organized criticality?

Accepted Answer

The tendency of some systems to settle into a balanced critical state where a single small event can trigger a cascade of any size. The sandpile is the textbook example; the same idea models earthquakes, forest fires and avalanches.

Question 3

Can I reset the sandpile?

Accepted Answer

Yes. Reload the page to clear the grid and start a new pile from empty. Nothing is saved, so every run is a one-off.

Sandpile — a live Bak–Tang–Wiesenfeld abelian sandpile that grows and avalanches forever; self-organized criticality, live in your browser.