Researchers have discovered that a remarkable diversity of complex networks, including the World Wide Web and patterns in cellular biochemistry, have a common architecture with snowflakes and trees. These networks all display similar patterns, whether viewed from up close or far away.
"It's a fundamental advance," says Albert-László Barabási, a physicist who studies networks at the University of Notre Dame in Indiana. The question of whether complex networks can show such a fractal pattern, also known as self-similarity, "has been bugging us for a while," he says.
In recent years, researchers have found that a surprising range of networks has a common structure: