Google recently added to its search a function where, when a person types in any actor’s name followed by “bacon number,” it will display that actor’s Bacon Number.  This number represents the degrees of movie separation between that actor and actor Kevin Bacon.  Originally it had been assumed that there would be a maximum of six degrees of separation between any actor and Kevin Bacon, but now finding anyone with a Bacon Number greater than three is difficult.

Likewise, we had assumed that there were six degrees of separation between everyone and anybody else in the world.  However, through Facebook, we can see that there are closer to only three degrees of separation between Facebook users.

In class, we discussed that there was a good likelihood that the graph of friends among humanity is not completely closed, but that there is almost surely not a second giant component.  While there is no way to prove this, at least in the acting subset of people we can be sure that there are very few degrees of separation between actors, and no second giant component.

Six degrees of Kevin Bacon is not a very valid survey sample to model the way that large networks are completely closed.  This is because that, to be considered in this sample, an actor  needs to be interacting with other actors.  The reason that large networks are closed is that there is a high likelihood that there is at least one person in a large enough group who will be a hermit and not interact with anyone else.

However, it is a good model to explain why there is not a second giant component.  All it takes is one person who had been in a movie with Kevin Bacon to make everyone they are in a movie with connected to Kevin Bacon, and through Kevin Bacon they are connected with everyone else.

-Zinny