Reading up on ETH Zürich

1 deep · digging since sep 24

A single ball on a fixed table can compute: Eva Miranda and Isaac Ramos prove that two-dimensional billiards are Turing complete - Centre de Recerca Matemàtica
A single point particle bouncing in a fixed planar billiard table can simulate a universal Turing machine, proving two‑dimensional billiards are computationally universal.