Does anyone know about a theory that states everyone is 7 persons away from another person?

Question

Or something like that.. sorry if it's a bit confusing the way I explain it: there was a theory that was based on calculations that said something like let's say Rosalind lives in Arizona and Bob in Brazil, there are only 7 people in between them in order for them to meet. The theory applies to everyone in the world regardless. Does anyone know more precisely about this theory? Many many thanks!

Answer 1

There are two things to that:

1)  "A recent electronic small world experiment at Columbia University found that about five to seven degrees of separation are sufficient for connecting any two people through e-mail.[8]"

Electronic Small World Experiment: Columbia.edu website; Six Degrees: The Science of a Connected Age, Duncan Watts. (via wikipedia)

2) There is six degree's of separation, which is a sociology concept. See:

http://en.wikipedia.org/wiki/Six_degrees...