Weak Links: Stabilizers of Complex Systems from Proteins to Social Networks. Peter Csermely. (2006, Springer.) Hardcover, $64.95, 410 pages

Abstract

Weak Links: Stabilizers of Complex Systems from Proteins to Social Networks. Peter Csermely. (2006, Springer.) Hardcover, $64.95, 410 pages. Following Barabasi’s Linked [1], network science has become a popular and effective method to study the range of complex systems from molecular interactions to friendship networks. Many measures have been developed to classify and analyze networks. These structural metrics tend to focus on the more permanent connections of a network. Peter Csermely takes a different stance, focusing his book on those connections whose presence does not change the value of these measures in a ‘‘statistically discernible way’’ (p. 3)—the weak links. In contrast to the predominant emphasis on the more easily measured connections of a system, Weak Links focuses on the effervescent edges that make a network both dynamic and, in his opinion, stable. Csermely advocates a serious exploration of the stabilizing role of weak links in networks at all levels. Csermely posits the stabilizing effect of weak links to be a general network property of all complex systems. This ambitious claim is substantiated by varied examples from many disciplines as well as through intriguing conjecture in areas that require further research. With a surprising combination of scientific exposition and philosophical reflection, Weak Links opens with a biochemical research problem and takes the reader through the breadth of network science studies to conclude with a larger message for humankind. The first half of the book attempts to fully explain the components of Csermely’s hypothesis. This is time well spent, considering the notoriously difficult-to-define topics he tackles—stability, complexity, and weakness. Through a review of other accepted general network properties, such as scale-freeness, clustering, and preferential attachment, Csermely introduces the role of weak links, setting them in a familiar context. In what is anything but a typical review of network science, he includes such diverse asides as fractal geometry, Levy flights in biology, and the scale-free properties of music. What follows is the most technical chapter of the book, exploring the meaning of stability in networks. He concludes that weak links protect networks from perturbations that test network stability. Albeit a difficult subject, the stability definition tends toward the anecdotal. The second half of the book involves a trip to Netland. Here, each chapter is devoted to the description of weak link stabilization in networks of a particular scale. The journey begins with a review of the literature indicating weak link stabilization in macromolecules and continues to cells, organisms, and social networks with each successive chapter. The most unique work ensues as the trip to Netland continues to cultural networks (including language and architecture), the global web