“Six Degrees of Kevin Bacon” Game Provides Clue to Efficiency of Complex Networks

How the hidden metric space guides communication. If node A wants to reach node F, it checks the hidden distances between F and its two neighbors B and C. Distance CF (green dashed line) is smaller than BF (red dashed line), therefore A forwards information to C. Node C then performs similar calculations and selects its neighbor D as the next hop on the path to F. Node D is directly connected to F. The result is path ACDF shown by green edges in the observable topology.

As the worldwide population continues to grow exponentially, our social connections to one another remain relatively modest, as if we’re all protagonists in the Kevin Bacon game inspired by “Six Degrees of Separation,” a Broadway play and Hollywood feature that were popular in the 1990s.

The truth is, classic studies reveal that if we were to route a letter to an unknown person using acquaintances or only friends who we thought might know the intended receiver, it could require six or five intermediary acquaintances prior to the letter reaches its planned destination.

The inherent success of the happening known as the “small-world paradigm,” found in the 1960s by sociologist Stanley Milgram, recently supplied a source of inspiration for researchers studying the World Wide Web as a worldwide elaborate network.

For these researchers, the notion of an inherent hidden space that is “hidden space” may also be important to their professional interests: how to remove bottlenecks that are mounting inside the Internet that endanger the simple passing of digital information round the world.

“Internet pros are worried the existing Internet routing design might not sustain even another decade,” said Krioukov, the study’s principal investigator using the Cooperative Association for Internet Data Analysis (CAIDA), based in the San Diego Supercomputer Center at the University of California, San Diego. “Routing in the existing Internet has already reached its scalability limits; black holes are appearing everywhere.”