Science books may be making a stronger showing at the beach this year. In June, Stephen Wolfram's 1,192-page self-published opus, A New Kind of Science, rose to the number one spot on Amazon's top 100 list despite a hefty price tag of $44.95 (Book News, June 24). Now Albert-Lásló Barabási's considerably thinner and less expensive Linked: The New Science of Networks (Perseus, June 1, 280p, $26) is also making the climb. After three trips back to press, there are just over 20,000 copies in print.

A professor of physics at the University of Notre Dame, Romanian-born Barabási is one of the leading researchers on networks. Cutting across a number of disciplines, his findings show that all networks, from cocktail parties to terrorist cells to the AIDS virus, follow the same pattern. Several of his explanations of business world phenomena—such as why Hotmail spread so rapidly and Cisco Systems' Internet supply chain failed—were highlighted in an article on Barabási in the Sunday New York Times business section on June 23. The day after the story ran, Linked rose to number 12 at Amazon, and has since hovered in the top 200.

Independents also report strong, steady sales. David Hartsough, manager of Cody's in Berkeley, Calif., told PW that the book is one of the better-selling hardcovers at his store. At the MIT Press Bookstore in Cambridge, Mass., Linked is number 10 on the store's bestseller list. "We're riding a crest from an event with Barabási," said co-manager John Jenkins, referring to Barabási's May appearance in the Authors @ MIT lecture series. "The book's really amazing, so we made it a staff pick."

Like Malcolm Gladwell in The Tipping Point, Barabási based his research on social scientist Stanley Milgram's 1967 study indicating that everyone in the world is just six handshakes away from everyone else. On the Web, Barabási found, people are only 19 clicks apart. And in an amusing variation on the Kevin Bacon game, porn stars are just 2.5 movies away from each other. But the similarity between the two books ends there. Barabási's 1999 discovery of the hubs that connect networks—much like the hubs in major cities that connect airlines—suggests that networks are not random, but are straight continuums guided by identifiable rules. Hence, there is no tipping point or threshold above which something succeeds or below which it fails. "If there were a tipping point, then you would find two groups of books—those that make it and sell several million copies and those that sell only a thousand copies. In between, there would be a vacuum." Barabási continues, "in the absence of a tipping point, hubs are very important. One book I like to think about is Sylvia Ann Hewlett's Creating a Life: Professional Women and the Quest for Children—that's a book that reached all the hubs, but no one was buying it. If an idea is less virulent, it will not go far from the hubs. More virulent ideas have a much higher chance of going further."

For Barabási, the biggest benefit of uncovering the structure of networks is the possibilities it creates for controlling disease. "I personally believe that in the next five to 10 years, the impact will be in medicine. That's why in the last year I've changed [from studying the World Wide Web] to biological research," he said.

The jury is out as to whether the ideas in Linked are genuinely contagious. But it has received coverage in some important media hubs, including an advance cover story in the April 13 issue of New Scientist and reviews in Fast Company, Nature and Time Out New York. In May, Barabási spoke at bookstores in several college communities—San Francisco; Boston; Ann Arbor, Mich.; South Bend, Ind.; and Chicago.