We are taught two ways to organize or create order: tables (via spreadsheets, lists, etc.) and hierarchical trees (organization of large companies, "folders and files" on a computer, etc.). But these approaches don't always work. Here's a couple of examples:
Tabular
You decide to make a a list of friends. You include info like birthday, phone number, address; so your list turns into a table. Then you add a column for spouse. But some of the spouses are friends that you want to include the other information. There are now links across rows and columns. Then you decide to add a "group" column: family, school, church, etc. Now there are extra links because a friend can belong to multiple "groups".Hierarchical Tree
You decide to organize your photos in folders. You have a folder for each year with sub-folders for Birthdays, Weddings, Holidays, Graduations, Parties, Concerts, Sporting Events, School Events, Vacations, Miscellaneous. Now, your family member is having a special event and you want to make a slide show of their life. You have to search through every folder (which can be hundreds). While you can find a photo for all birthdays in 2001, the organization doesn't help you find photos for a person.In large businesses that typically have a hierarchical management structure, many have turned to a "matrix organization" with links between groups.
Scale-Free Network
Scientists have known for a long time that there was some kind of network structure, but they didn't understand it until recently when computers and an abundance of data gave them the ability to discover the nature of networks. What they found is a "scale-free" network. A network is a bunch of nodes (people, websites, companies, or just about anything) connected together. A scale-free network has many nodes on the edges connected to just one or two other nodes. Some of these form tightly connected clusters. Many clusters and nodes are connected via hubs of progressively larger sizes.Why is it called "Scale-Free"? Basically, these networks can grow or "scale", "free" of a change in the network characteristics.
Examples of Scale-Free Networks:
- The Internet (whether you consider it a network of computers or web pages with links)
- Hollywood Actors (The "Kevin Bacon" effect, or actors that have been in movies with other actors)
- The Spread of Aids (via the sexual partner network).
- Metabolic network (the reactions of molecules in living cells)
- Snowflake
Why Scale-Free Networks Matter
"They are the patent signatures of self-organization in complex systems".We live in a complex world yet somehow the overall order arises when it wouldn't be expected. You've heard the saying "Life is what happens while you are busy making other plans". No one has the ability to control all circumstances in their life, yet self-organizing forces seem to pull it all together.
Another amazing property of scale-free networks is the idea of the "small-world". In a network of countless nodes, two nodes are separated by a surprisingly small number of links. While the magnitude in the world can be overwhelming, the pervasiveness of scale-free networks makes this truly "a small world after all".
This post is inspired by the book "Linked: How Everything Is Connected to Everything Else and What It Means for Business, Science, and Everyday Life" by Albert-laszlo Barabasi.