Directed Percolation Model (IMAGE) American Physical Society Caption This is an illustration of directed percolation in 1+1 dimensions: Activity percolates through open bonds (red lines), activating nearest neighbors and giving rise to a cluster of activity. Credit Illustration: Alan Stonebraker Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.