I recently had an interesting conversation about how the Internet is changing the structure of people's social graphs that I thought I would share here. I have written before about the concept of the "weak tie" (WT) in network analysis and the important role they play in the dissemination of information through social networks (link to Granovetter's Strength of WT paper). My recent conversation was about the extinction of "bridges" online. A bridge is formally defined as an edge within a graph that if deleted, would cause its endpoints to to lie in different components of a graph. An easier way to understand a bridge is to see the image to the right - the members of the two groups would have no connections to the other group if Bill and Mike did not have a relationship. Their connection is the bridge between the two groups.Building your social graph has become relatively frictionless online - the click of a button on a social network or the sending of an email creates a connection between you and another person, most of which would be classified as "weak ties". However, as our graphs expand and we interact with more people online, the concept of a bridge is beginning to face extinction. Interaction used to have physical limitations before the Internet, and as the web and specifically social media evolves, our interactions with people are increasing exponentially. While bridges are far from being extinct - our world's population is around 7B and world Internet population is around 1.67B as of June 2009 according to Miniwatts Marketing Group - it will inevitably happen at some point. In fact, once global internet use rises above 50-60%, the extinction of bridges will be expedited significantly.
So what does this mean for theories like Granovetter's and the overall social structure with regards to the dissemination of information? Well, starting with the first part of the question, Granovetter's theory will still hold. Good information will still pass through weak ties, since your strong ties typically have access to much of the same information that you do which does not lead to the discovery of new things. Granovetter simply used the concept of a bridge to validate a weak tie within a network, so future studies of information dissemination will have to find more sophisticated ways to determine the strength of people's relationships - such as measuring the amount of times people interact through different platforms, how they interact, what they share, etc. The range of measurements on ties will increase, and we will see many more relational classifications. Many fascinating theories and insights will come from these advanced studies. We will begin to see a rapid increase in these starting in the next 2-3 years.
The effect on the overall social structure that the extinction of bridges will have is already starting to show. It is democratizing. It allows for the free and open exchange of information and ideas that in the past was stymied by physical restraints of delivery and production systems, as well as oppressive people with power over others - the production and delivery restraints and pretty much gone, and oppression will struggle to survive as the world becomes mores connected. I believe movements like those seen in Iran will become more commonplace as coordination and communication between peoples online is very hard to prevent. Bridge extinction is bringing incredible collaboration and competition to just about everything in the world. Typically in the past bridges were symbols of connection and progress, however in the digital age we live in, it is the extinction of bridges that is bringing people from all over the world closer together for good.
