Linked

May 27, 2002
Information, disease, knowledge and just about everything else is disseminated through a complex series of networks made up of interconnected hubs, argues University of Notre Dame physics professor Barabási. These networks are replicated in every facet of human life: "There is a path between any two neurons in our brain, between any two companies in the world, between any two chemicals in our body. Nothing is excluded from this highly interconnected web of life." In accessible prose, Barabási guides readers through the mathematical foundation of these networks. He shows how they operate on the Power Law, the notion that "a few large events carry most of the action." The Web, for example, is "dominated by a few very highly connected nodes, or hubs... such as Yahoo! or Amazon.com." Barabási notes that "the fittest node will inevitably grow to become the biggest hub." The elegance and efficiency of these structures also makes them easy to infiltrate and sabotage; Barabási looks at modern society's vulnerability to terrorism, and at the networks formed by terrorist groups themselves. The book also gives readers a historical overview on the study of networks, which goes back to 18th-century Swiss mathematician Leonhard Euler and includes the well-known "six degrees phenomenon" developed in 1967 by sociology professor Stanley Milgram. The book may remind readers of Steven Johnson's Emergence
and—with its emphasis on the mathematical underpinnings of social behavior—Malcolm Gladwell's The Tipping Point
(which Barabási discusses); those who haven't yet had their fill of this new subgenre should be interested in Barabási's lively and ambitious account.

June 1, 2002
Highlighted in Mark Buchanan's " Nexus" [BKL My 1 02] as a key researcher on networks, Barabasi here talks about his work in more detail. In an anecdotal narrative, he traces networks' mathematical parentage back to Leonhard Euler and the late Paul Erdos, two biographically as well as mathematically interesting geniuses. They set a foundation called graph theory, on which some sociologists in the late 1960s and early 1970s built ideas of how a social network functions; the phrase "six degrees of separation" arose out of their work. Amusing readers with what helped boost that phrase into general circulation--a Web site that calculates the movie-credit connections between Kevin Bacon and any other Hollywood actor--Barabasi then shifts to his own fascinating studies of the Web. His research group found that its domination by hub sites like Hotmail or Yahoo adheres to a graphical relation called the "power law." Limning this property in contexts such as Vernon Jordan's links among corporate boards, Barabasi imparts the central concepts of networks.(Reprinted with permission of Booklist, copyright 2002, American Library Association.)