The physics of the Web

July 14, 2001 | Source: Physics World

Statistical mechanics is offering new insights into the structure and dynamics of the Internet, the World Wide Web and other complex interacting systems.

The challenge for physicists is to unearth the signatures of order from the apparent chaos of millions of nodes and links.

Findings include:

* The Web is a scale-free network whose links follow a power-law distribution, which implies that there is an abundance of nodes with only a few links, and a small but significant ­ minority that have a very large number of links.

* The typical number of clicks between two Web pages is about 19, despite the fact that there are now over one billion pages out there.

* A node rich in links increases its connectivity faster than the rest of the nodes because incoming nodes link to it with higher probability. This “rich-gets-richer” phenomenon is present in many competitive systems.

* The improved understanding of real networks might provide new insights into the spread of ideas and biological viruses among the human population.

* Scale-free networks appear to be the architecture of choice for nature when it comes to complex systems. The metabolic and the ­protein interaction networks of cells follow a scale-free topology in all investigated organisms.